ngspice/src/frontend/com_measure2.c

/* New routines to evaluate the .measure cards.
   Entry point is function get_measure2(), called by fcn do_measure()
   from measure.c.
   Patches by Bill Swartz from 2009-05-18 and 2009-08-21 are included.
*/

#include "ngspice/ngspice.h"
#include "ngspice/memory.h"

#include "ngspice/fteext.h"
#include "ngspice/wordlist.h"

#include "vectors.h"
#include <math.h>
#include "dotcards.h"
#include "com_measure2.h"
#include "breakp2.h"

typedef enum {
    MEASUREMENT_OK = 0,
    MEASUREMENT_FAILURE = 1
} MEASURE_VAL_T;

#define MEASURE_DEFAULT -1
#define MEASURE_LAST_TRANSITION  -2

typedef struct measure
{
    char *result;

    char *m_vec;          // name of the output variable which determines the beginning of the measurement
    char *m_vec2;         // second output variable to measure if applicable
    char *m_analysis;     // analysis type (tran, dc or ac)
    char m_vectype;       // type of vector m_vec (vm, vi, vr, vp, vdb)
    char m_vectype2;      // type of vector m_vec2 (vm, vi, vr, vp, vdb)
    int m_rise;           // count number of rise events
    int m_fall;           // count number of fall events
    int m_cross;          // count number of rise/fall aka cross  events
    double m_val;         // value of the m_ver at which the counter for crossing, rises or falls is incremented by one
    double m_td;          // amount of delay before the measurement should start
    double m_from;        // measure only in a time window - starting time of window
    double m_to;          // measurement window - ending time
    double m_at;          // measure at the specified time
    double m_measured;    // what we measured
    double m_measured_at; // what we measured at the given time

} MEASURE, *MEASUREPTR;

typedef enum AnalysisType {
    AT_UNKNOWN, AT_DELAY, AT_TRIG,
    AT_FIND, AT_WHEN,
    AT_AVG, AT_MIN, AT_MAX, AT_RMS, AT_PP,
    AT_INTEG, AT_DERIV,
    AT_ERR, AT_ERR1, AT_ERR2, AT_ERR3, AT_MIN_AT, AT_MAX_AT
} ANALYSIS_TYPE_T;


/** return precision (either 5 or value of environment variable NGSPICE_MEAS_PRECISION) */
int
measure_get_precision(void)
{
    char *env_ptr;
    int  precision = 5;

    if ((env_ptr = getenv("NGSPICE_MEAS_PRECISION")) != NULL)
        precision = atoi(env_ptr);

    return precision;
}


static void
measure_errMessage(char *mName, char *mFunction, char *trigTarg, char *errMsg, int chk_only)
{
    if (!chk_only) {
        printf("\nError: measure  %s  %s(%s) : ", mName, mFunction, trigTarg);
        printf("%s", errMsg);
        // printf("\tmeasure '%s'  failed\n", mName);
    }
}


/* If you have a vector vm(out), extract 'm' to meas->m_vectype
   and v(out) to meas->m_vec (without 'm') */

static void
correct_vec(MEASUREPTR meas)
{
    char *vec = meas->m_vec;

    /* return if not of type VM() etc */
    if ((*vec != 'v') || (!strchr(vec, '(')))
        return;

    if (vec[1] != '(') {
        meas->m_vectype = vec[1];
        meas->m_vec = tprintf("%c%s", vec[0], strchr(vec, '('));
        tfree(vec);
    }

    vec = meas->m_vec2;

    if (vec && (vec[1] != '(')) {
        meas->m_vectype2 = vec[1];
        meas->m_vec2 = tprintf("%c%s", vec[0], strchr(vec, '('));
        tfree(vec);
    }
}


/* Returns a value from a complex vector *values, depending on meas->m_vectype */
static double
get_value(
    MEASUREPTR meas,     /*in: pointer to mesurement structure */
    struct dvec *values, /*in: vector of complex values */
    int idx              /*in: index of vector value to be read out */
    )
{
    double ar, bi;

    ar = values->v_compdata[idx].cx_real;
    bi = values->v_compdata[idx].cx_imag;

    if ((meas->m_vectype == 'm') || (meas->m_vectype == 'M')) {
        return hypot(ar, bi); /* magnitude */
    } else if ((meas->m_vectype == 'r') || (meas->m_vectype == 'R')) {
        return ar;  /* real value */
    } else if ((meas->m_vectype == 'i') || (meas->m_vectype == 'I')) {
        return bi;  /* imaginary value */
    } else if ((meas->m_vectype == 'p') || (meas->m_vectype == 'P')) {
        return radtodeg(atan2(bi, ar)); /* phase (in degrees) */
    } else if ((meas->m_vectype == 'd') || (meas->m_vectype == 'D')) {
        return 20.0 * log10(hypot(ar, bi));  /* dB of magnitude */
    } else {
        return ar;  /* default: real value */
    }
}


/* Returns interpolated value. If ac simulation, exploit vector type with complex data for y */
static double
measure_interpolate(
    struct dvec *xScale, /* in: vector of independent variables, if ac: complex vector,
                            but only real part used */
    struct dvec *values, /* in: vector of dependent variables, if ac: complex vector */
    int i,               /* in: index of first interpolation value */
    int j,               /* in: index of second interpolation value */
    double var_value,    /* in: variable, whose counterpart is sought by interpolation */
    char x_or_y ,        /* in: if 'x', then look for y, if 'y' then look for x */
    MEASUREPTR meas      /* pointer to measurement structure */
    )
{
    double slope;
    double yint;
    double result;

    if (cieq (meas->m_analysis, "ac")) {
        /* get values from complex y vector according to meas->m_vectype,
           x vector uses only real part of complex data (frequency).*/
        slope = (get_value(meas, values, j)  - get_value(meas, values, i)) /
            (xScale->v_compdata[j].cx_real - xScale->v_compdata[i].cx_real);
        yint  = get_value(meas, values, i) - slope*xScale->v_compdata[i].cx_real;
    } else {
        slope = (values->v_realdata[j] - values->v_realdata[i]) /
            (xScale->v_realdata[j] - xScale->v_realdata[i]);
        yint  = values->v_realdata[i] - slope*xScale->v_realdata[i];
    }

    if (x_or_y == 'x')
        result = (var_value - yint)/slope;
    else
        result = slope*var_value + yint;

    return result;
}


/* -----------------------------------------------------------------
 * Function: Given an operation string returns back the measure type -
 * one of the enumerated type ANALSYS_TYPE_T.
 * ----------------------------------------------------------------- */
static ANALYSIS_TYPE_T
measure_function_type(char *operation)
{
    char *mFunction;               /* operation */
    ANALYSIS_TYPE_T mFunctionType; /* type of requested function */

    mFunction = cp_unquote(operation);
    // Functions
    if (strcasecmp(mFunction, "DELAY") == 0)
        mFunctionType = AT_DELAY;
    else if (strcasecmp(mFunction, "TRIG") == 0)
        mFunctionType = AT_DELAY;
    else if (strcasecmp(mFunction, "TARG") == 0)
        mFunctionType = AT_DELAY;
    else if (strcasecmp(mFunction, "FIND") == 0)
        mFunctionType = AT_FIND;
    else if (strcasecmp(mFunction, "WHEN") == 0)
        mFunctionType = AT_WHEN;
    else if (strcasecmp(mFunction, "AVG") == 0)
        mFunctionType = AT_AVG;
    else if (strcasecmp(mFunction, "MIN") == 0)
        mFunctionType = AT_MIN;
    else if (strcasecmp(mFunction, "MAX") == 0)
        mFunctionType = AT_MAX;
    else if (strcasecmp(mFunction, "MIN_AT") == 0)
        mFunctionType = AT_MIN_AT;
    else if (strcasecmp(mFunction, "MAX_AT") == 0)
        mFunctionType = AT_MAX_AT;
    else if (strcasecmp(mFunction, "RMS") == 0)
        mFunctionType = AT_RMS;
    else if (strcasecmp(mFunction, "PP") == 0)
        mFunctionType = AT_PP;
    else if (strcasecmp(mFunction, "INTEG") == 0)
        mFunctionType = AT_INTEG;
    else if (strcasecmp(mFunction, "DERIV") == 0)
        mFunctionType = AT_DERIV;
    else if (strcasecmp(mFunction, "ERR") == 0)
        mFunctionType = AT_ERR;
    else if (strcasecmp(mFunction, "ERR1") == 0)
        mFunctionType = AT_ERR1;
    else if (strcasecmp(mFunction, "ERR2") == 0)
        mFunctionType = AT_ERR2;
    else if (strcasecmp(mFunction, "ERR3") == 0)
        mFunctionType = AT_ERR3;
    else
        mFunctionType = AT_UNKNOWN;

    tfree(mFunction);

    return (mFunctionType);
}


/* -----------------------------------------------------------------
 * Function: Parse the measurement line and extract any variables in
 * the statement and call com_save2 to instantiate the variable as a
 * measurement vector in the transient analysis.
 * ----------------------------------------------------------------- */
int
measure_extract_variables(char *line)
{
    /* Various formats for measure statement:
     * .MEASURE {DC|AC|TRAN} result TRIG trig_variable VAL=val
     * + <TD=td> <CROSS=# | CROSS=LAST> <RISE=#|RISE=LAST> <FALL=#|FALL=LAST>
     * + <TRIG AT=time>
     * + TARG targ_variable VAL=val
     * + <TD=td> <CROSS=# | CROSS=LAST> <RISE=#|RISE=LAST> <FALL=#|FALL=LAST>
     * + <TRIG AT=time>
     *
     * .MEASURE {DC|AC|TRAN} result WHEN out_variable=val
     * + <TD=td> <FROM=val> <TO=val>
     * + <CROSS=# | CROSS=LAST> <RISE=#|RISE=LAST> <FALL=#|FALL=LAST>
     *
     * .MEASURE {DC|AC|TRAN} result WHEN out_variable=out_variable2
     * + <TD=td> <FROM=val> <TO=val>
     * + <CROSS=# | CROSS=LAST> <RISE=#|RISE=LAST> <FALL=#|FALL=LAST>
     *
     * .MEASURE {DC|AC|TRAN} result FIND out_variable WHEN out_variable2=val
     * + <TD=td> <FROM=val> <TO=val>
     * + <CROSS=# | CROSS=LAST> <RISE=#|RISE=LAST> <FALL=#|FALL=LAST>
     *
     * .MEASURE {DC|AC|TRAN} result FIND out_variable WHEN out_variable2=out_variable3
     * + <TD=td>
     * + <CROSS=# | CROSS=LAST> <RISE=#|RISE=LAST> <FALL=#|FALL=LAST>
     *
     * .MEASURE {DC|AC|TRAN} result FIND out_variable AT=val
     * + <FROM=val> <TO=val>
     *
     * .MEASURE {DC|AC|TRAN} result {AVG|MIN|MAX|MIN_AT|MAX_AT|PP|RMS} out_variable
     * + <TD=td> <FROM=val> <TO=val>
     *
     * .MEASURE {DC|AC|TRAN} result INTEG<RAL> out_variable
     * + <TD=td> <FROM=val> <TO=val>
     *
     * .MEASURE {DC|AC|TRAN} result DERIV<ATIVE> out_variable AT=val
     *
     * .MEASURE {DC|AC|TRAN} result DERIV<ATIVE> out_variable WHEN out_variable2=val
     * + <TD=td>
     * + <CROSS=# | CROSS=LAST> <RISE=#|RISE=LAST> <FALL=#|FALL=LAST>
     *
     * .MEASURE {DC|AC|TRAN} result DERIV<ATIVE> out_variable WHEN out_variable2=out_variable3
     * + <TD=td>
     * + <CROSS=# | CROSS=LAST> <RISE=#|RISE=LAST> <FALL=#|FALL=LAST>
     * ----------------------------------------------------------------- */

    int status;                 /* return status */
    char *item;                 /* parsing item */
    char *measure;              /* measure keyword */
    char *analysis;             /* analysis option */
    char *variable, *variable2; /* variable to trace */
    wordlist *measure_var;      /* wordlist of measurable */
    ANALYSIS_TYPE_T op;         /* measure function type */

    status = TRUE;
    measure = gettok(&line);
    if (!measure)
        return (status);

    analysis = gettok(&line);
    if (!analysis)
        return (status);

    if ((strcasecmp(analysis, "DC") == 0) ||
        (strcasecmp(analysis, "AC") == 0) ||
        (strcasecmp(analysis, "TRAN") == 0)) {
        analysis = copy(analysis);
    } else {
        /* sometimes operation is optional - for now just pick trans */
        analysis = copy("TRAN");
    }

    do {
        item = gettok(&line);
        if (item) {
            op = measure_function_type(item);
            if (op != AT_UNKNOWN) {
                /* We have a variable/complex variable coming next */
                variable = gettok_iv(&line);
                variable2 = NULL;
                if (*line == '=')
                    variable2 = gettok_iv(&line);
                if (variable) {
                    size_t len = strlen(item);
                    if (item[len-1] == '=') {
                    } else {
                        /* We may have something like V(n1)=1
                           or v(n1)=2 , same with i() */
                        measure_var = gettoks(variable);
                        com_save2(measure_var, analysis);
                        status = FALSE;
                    }
                }
                if (variable2) {
                    /* We may have something like  v(n1)=v(n2)
                       v(n2) is handled here, same with i() */
                    measure_var = gettoks(variable2);
                    com_save2(measure_var, analysis);
                    status = FALSE;
                }
            }
        }
    } while(line && *line);

    return (status);
}


/* -----------------------------------------------------------------
 * Function: process a WHEN measurement statement which has been
 * parsed into a measurement structure.
 * ----------------------------------------------------------------- */
static void
com_measure_when(
    MEASUREPTR meas     /* in : parsed measurement structure */
    )
{
    int i, first;
    int riseCnt = 0;
    int fallCnt = 0;
    int crossCnt = 0;
    int section = -1;
    int measurement_pending;
    int init_measured_value;
    bool ac_check = FALSE, sp_check = FALSE, dc_check = FALSE, tran_check = FALSE;
    bool has_d2 = FALSE;
    double value, prevValue, value2, prevValue2;
    double scaleValue, prevScaleValue;

    enum ValSide { S_ABOVE_VAL, S_BELOW_VAL };
    enum ValEdge { E_RISING, E_FALLING };

    struct dvec *d, *d2, *dScale;

    d = vec_get(meas->m_vec);

    if (meas->m_vec2) {
        d2 = vec_get(meas->m_vec2);
        has_d2 = TRUE;
    } else {
        d2 = NULL;
    }

    dScale = plot_cur->pl_scale;

    if (d == NULL) {
        fprintf(cp_err, "Error: no such vector as %s.\n", meas->m_vec);
        return;
    }

    if (has_d2 && (d2 == NULL)) {
        fprintf(cp_err, "Error: no such vector as %s.\n", meas->m_vec2);
        return;
    }
    if (dScale == NULL) {
        fprintf(cp_err, "Error: no scale vector.\n");
        return;
    }

    prevValue = 0.;
    prevValue2 = 0.;
    prevScaleValue = 0.;
    first = 0;
    measurement_pending = 0;
    init_measured_value = 1;


    /* -----------------------------------------------------------------
     * Take the string tests outside of the loop for speed.
     * ----------------------------------------------------------------- */
    if (cieq (meas->m_analysis, "ac"))
        ac_check = TRUE;
    else if (cieq (meas->m_analysis, "sp"))
        sp_check = TRUE;
    else if (cieq (meas->m_analysis, "dc"))
        dc_check = TRUE;
    else
        tran_check = TRUE;

    for (i = 0; i < d->v_length; i++) {

        if (ac_check) {
            if (d->v_compdata)
                value = get_value(meas, d, i); //d->v_compdata[i].cx_real;
            else
                value = d->v_realdata[i];
            scaleValue = dScale->v_compdata[i].cx_real;
        } else if (sp_check) {
            if (d->v_compdata)
                value = get_value(meas, d, i); //d->v_compdata[i].cx_real;
            else
                value = d->v_realdata[i];
            scaleValue = dScale->v_realdata[i];
        } else {
            value = d->v_realdata[i];
            scaleValue = dScale->v_realdata[i];
        }

        if (has_d2) {
            if (ac_check) {
                if (d2->v_compdata)
                    value2 = get_value(meas, d2, i); //d->v_compdata[i].cx_real;
                else
                    value2 = d2->v_realdata[i];
            } else if (sp_check) {
                if (d2->v_compdata)
                    value2 = get_value(meas, d2, i); //d->v_compdata[i].cx_real;
                else
                    value2 = d2->v_realdata[i];
            } else {
                value2 = d2->v_realdata[i];
            }
        } else {
            value2 = NAN;
        }

        /* 'dc' is special: it may start at an arbitrary scale value.
           Use m_td to store this value, a delay TD does not make sense */
        if (dc_check && (i == 0))
            meas->m_td = scaleValue;
        /* if analysis tran, suppress values below TD */
        if (tran_check && (scaleValue < meas->m_td))
            continue;
        /* if analysis ac, sp, suppress values below 0 */
        else if ((ac_check || sp_check) && (scaleValue < 0))
            continue;

        /* if 'dc': reset first if scale jumps back to origin */
        if ((first > 1) && (dc_check && (meas->m_td == scaleValue)))
            first = 1;

        if (first == 1) {
            if (has_d2) {
                // initialise
                crossCnt = 0;
                if (value < value2) {
                    section = S_BELOW_VAL;
                    if ((prevValue <= value2) && (value >= value2)) {
                        fallCnt = 1;
                        crossCnt = 1;
                    }

                } else {
                    section = S_ABOVE_VAL;
                    if ((prevValue <= value2) && (value >= value2)) {
                        riseCnt = 1;
                        crossCnt = 1;
                    }
                }
                fflush(stdout);
            } else {
                // initialise
                crossCnt = 0;
                if (value < meas->m_val) {
                    section = S_BELOW_VAL;
                    if ((prevValue <= meas->m_val) && (value >= meas->m_val)) {
                        fallCnt = 1;
                        crossCnt = 1;
                    }

                } else {
                    section = S_ABOVE_VAL;
                    if ((prevValue <= meas->m_val) && (value >= meas->m_val)) {
                        riseCnt = 1;
                        crossCnt = 1;
                    }
                }
                fflush(stdout);
            }
        }

        if (first > 1) {
            if (has_d2) {
                if ((section == S_BELOW_VAL) && (value >= value2)) {
                    section = S_ABOVE_VAL;
                    crossCnt++;
                    riseCnt++;
                    if (meas->m_fall != MEASURE_LAST_TRANSITION) {
                        /* we can measure rise/cross transition if the user
                         * has not requested a last fall transition */
                        measurement_pending = 1;
                    }

                } else if ((section == S_ABOVE_VAL) && (value <= value2)) {
                    section = S_BELOW_VAL;
                    crossCnt++;
                    fallCnt++;
                    if (meas->m_rise != MEASURE_LAST_TRANSITION) {
                        /* we can measure fall/cross transition if the user
                         * has not requested a last rise transition */
                        measurement_pending = 1;
                    }
                }

                if  ((crossCnt == meas->m_cross) || (riseCnt == meas->m_rise) || (fallCnt == meas->m_fall)) {
                    /* user requested an exact match of cross, rise, or fall
                     * exit when we meet condition */
//                meas->m_measured = prevScaleValue + (value2 - prevValue) * (scaleValue - prevScaleValue) / (value - prevValue);
                    meas->m_measured = prevScaleValue + (prevValue2 - prevValue) * (scaleValue - prevScaleValue) / (value - prevValue - value2 + prevValue2);
                    return;
                }
                if  (measurement_pending) {
                    if ((meas->m_cross == MEASURE_DEFAULT) && (meas->m_rise == MEASURE_DEFAULT) && (meas->m_fall == MEASURE_DEFAULT)) {
                        /* user didn't request any option, return the first possible case */
                        meas->m_measured = prevScaleValue + (prevValue2 - prevValue) * (scaleValue - prevScaleValue) / (value - prevValue - value2 + prevValue2);
                        return;
                    } else if ((meas->m_cross == MEASURE_LAST_TRANSITION) || (meas->m_rise == MEASURE_LAST_TRANSITION) || (meas->m_fall == MEASURE_LAST_TRANSITION)) {
                        meas->m_measured = prevScaleValue + (prevValue2 - prevValue) * (scaleValue - prevScaleValue) / (value - prevValue - value2 + prevValue2);
                        /* no return - look for last */
                        init_measured_value = 0;
                    }
                    measurement_pending = 0;
                }
            } else {
                if ((section == S_BELOW_VAL) && (value >= meas->m_val)) {
                    section = S_ABOVE_VAL;
                    crossCnt++;
                    riseCnt++;
                    if (meas->m_fall != MEASURE_LAST_TRANSITION) {
                        /* we can measure rise/cross transition if the user
                         * has not requested a last fall transition */
                        measurement_pending = 1;
                    }

                } else if ((section == S_ABOVE_VAL) && (value <= meas->m_val)) {
                    section = S_BELOW_VAL;
                    crossCnt++;
                    fallCnt++;
                    if (meas->m_rise != MEASURE_LAST_TRANSITION) {
                        /* we can measure fall/cross transition if the user
                         * has not requested a last rise transition */
                        measurement_pending = 1;
                    }
                }

                if  ((crossCnt == meas->m_cross) || (riseCnt == meas->m_rise) || (fallCnt == meas->m_fall)) {
                    /* user requested an exact match of cross, rise, or fall
                     * exit when we meet condition */
                    meas->m_measured = prevScaleValue + (meas->m_val - prevValue) * (scaleValue - prevScaleValue) / (value - prevValue);
                    return;
                }
                if  (measurement_pending) {
                    if ((meas->m_cross == MEASURE_DEFAULT) && (meas->m_rise == MEASURE_DEFAULT) && (meas->m_fall == MEASURE_DEFAULT)) {
                        /* user didn't request any option, return the first possible case */
                        meas->m_measured = prevScaleValue + (meas->m_val - prevValue) * (scaleValue - prevScaleValue) / (value - prevValue);
                        return;
                    } else if ((meas->m_cross == MEASURE_LAST_TRANSITION) || (meas->m_rise == MEASURE_LAST_TRANSITION) || (meas->m_fall == MEASURE_LAST_TRANSITION)) {
                        meas->m_measured = prevScaleValue + (meas->m_val - prevValue) * (scaleValue - prevScaleValue) / (value - prevValue);
                        /* no return - look for last */
                        init_measured_value = 0;
                    }
                    measurement_pending = 0;
                }
            }
        }
        first ++;

        prevValue = value;
        if (has_d2)
            prevValue2 = value2;
        prevScaleValue = scaleValue;
    }

    if (init_measured_value)
        meas->m_measured = NAN;
}


/* -----------------------------------------------------------------
 * Function: process an AT measurement statement which has been
 * parsed into a measurement structure.  We make sure to interpolate
 * the value when appropriate.
 * ----------------------------------------------------------------- */
static void
measure_at(
    MEASUREPTR meas,            /* in : parsed "at" data */
    double at                   /* in: time to perform measurement */
    )
{
    int i;
    double value, pvalue, svalue, psvalue;
    bool ac_check = FALSE, sp_check = FALSE, dc_check = FALSE, tran_check = FALSE;
    struct dvec *d, *dScale;

    psvalue = pvalue = 0;
    d = vec_get(meas->m_vec);
    dScale = plot_cur->pl_scale;

    if (d == NULL) {
        fprintf(cp_err, "Error: no such vector as %s.\n", meas->m_vec);
        return;
    }

    if (dScale == NULL) {
        fprintf(cp_err, "Error: no such vector time, frequency or dc.\n");
        return;
    }

    /* -----------------------------------------------------------------
     * Take the string tests outside of the loop for speed.
     * ----------------------------------------------------------------- */
    if (cieq (meas->m_analysis, "ac"))
        ac_check = TRUE;
    else if (cieq (meas->m_analysis, "sp"))
        sp_check = TRUE;
    else if (cieq (meas->m_analysis, "dc"))
        dc_check = TRUE;
    else
        tran_check = TRUE;

    for (i = 0; i < d->v_length; i++) {
        if (ac_check) {
            if (d->v_compdata) {
                value = get_value(meas, d, i); //d->v_compdata[i].cx_real;
            } else {
                value = d->v_realdata[i];
                // fprintf(cp_err, "Warning: 'meas ac' input vector is real!\n");
            }
            svalue = dScale->v_compdata[i].cx_real;
        } else if (sp_check) {
            if (d->v_compdata)
                value = get_value(meas, d, i); //d->v_compdata[i].cx_real;
            else
                value = d->v_realdata[i];
            svalue = dScale->v_realdata[i];
        } else {
            value = d->v_realdata[i];
            svalue = dScale->v_realdata[i];
        }

        if ((i > 0) && (psvalue <= at) && (svalue >= at)) {
            meas->m_measured = pvalue + (at - psvalue) * (value - pvalue) / (svalue - psvalue);
            return;
        } else if  (dc_check && (i > 0) && (psvalue >= at) && (svalue <= at)) {
            meas->m_measured = pvalue + (at - psvalue) * (value - pvalue) / (svalue - psvalue);
            return;
        }

        psvalue = svalue;
        pvalue = value;
    }

    meas->m_measured = NAN;
}


/* -----------------------------------------------------------------
 * Function: process an MIN, MAX, or AVG statement which has been
 * parsed into a measurement structure.  We should make sure to interpolate
 * the value here when we have m_from and m_to constraints * so this
 * function is slightly wrong.   Need to fix in future rev.
 * ----------------------------------------------------------------- */
static void
measure_minMaxAvg(
    MEASUREPTR meas,                /* in : parsed measurement data request */
    ANALYSIS_TYPE_T mFunctionType   /* in: one of AT_AVG, AT_MIN, AT_MAX, AT_MIN_AT, AT_MAX_AT */
    )
{
    int i;
    struct dvec *d, *dScale;
    double value, svalue, mValue, mValueAt;
    double pvalue = 0.0, sprev = 0.0, Tsum = 0.0;
    int first;
    bool ac_check = FALSE, sp_check = FALSE, dc_check = FALSE, tran_check = FALSE;

    mValue = 0;
    mValueAt = svalue = 0;
    meas->m_measured = NAN;
    meas->m_measured_at = NAN;
    first = 0;

    d = vec_get(meas->m_vec);
    if (d == NULL) {
        fprintf(cp_err, "Error: no such vector as %s.\n", meas->m_vec);
        return;
    }


    /* -----------------------------------------------------------------
     * Take the string tests outside of the loop for speed.
     * ----------------------------------------------------------------- */
    if (cieq (meas->m_analysis, "ac"))
        ac_check = TRUE;
    else if (cieq (meas->m_analysis, "sp"))
        sp_check = TRUE;
    else if (cieq (meas->m_analysis, "dc"))
        dc_check = TRUE;
    else
        tran_check = TRUE;

    if (ac_check || sp_check) {
        dScale = vec_get("frequency");
    } else if (tran_check) {
        dScale = vec_get("time");
    } else if (dc_check) {
        dScale = vec_get("v-sweep");
    } else {                    /* error */
        fprintf(cp_err, "Error: no such analysis type as %s.\n", meas->m_analysis);
        return;
    }

    if (dScale == NULL) {
        fprintf(cp_err, "Error: no such vector as time, frquency or v-sweep.\n");
        return;
    }

    for (i = 0; i < d->v_length; i++) {
        if (ac_check) {
            if (d->v_compdata) {
                value = get_value(meas, d, i); //d->v_compdata[i].cx_real;
            } else {
                value = d->v_realdata[i];
                // fprintf(cp_err, "Warning: 'meas ac' input vector is real!\n");
            }
            svalue = dScale->v_compdata[i].cx_real;
        } else if (sp_check) {
            if (d->v_compdata)
                value = get_value(meas, d, i); //d->v_compdata[i].cx_real;
            else
                value = d->v_realdata[i];
            svalue = dScale->v_realdata[i];
        } else {
            value = d->v_realdata[i];
            svalue = dScale->v_realdata[i];
        }

        if (dc_check) {
            /* dc: start from pos or neg scale value */
            if ((svalue < meas->m_from) || (svalue > meas->m_to))
                continue;
        } else {
            /* all others: start from neg scale value */
            if (svalue < meas->m_from)
                continue;

            if ((meas->m_to != 0.0e0) && (svalue > meas->m_to))
                break;
        }

        if (first == 0) {
            first = 1;

            switch (mFunctionType) {
            case AT_MIN:
            case AT_MIN_AT:
            case AT_MAX_AT:
            case AT_MAX:
                mValue = value;
                mValueAt = svalue;
                break;
            case AT_AVG:
                mValue = 0.0;
                mValueAt = svalue;
                Tsum = 0.0;
                pvalue = value;
                sprev = svalue;
                break;
            default:
                fprintf(cp_err, "Error: improper min/max/avg call.\n");
            }
        } else {
            switch (mFunctionType) {
            case AT_MIN:
            case AT_MIN_AT: {
                if (value <= mValue) {
                    mValue = value;
                    mValueAt = svalue;
                }
                break;
            }
            case AT_MAX_AT:
            case AT_MAX: {
                if (value >= mValue) {
                    mValue = value;
                    mValueAt = svalue;
                }
                break;
            }
            case AT_AVG: {
                mValue += 0.5 * (value + pvalue) * (svalue - sprev);
                Tsum += (svalue - sprev);
                pvalue = value;
                sprev = svalue;
                break;
            }
            default :
                fprintf(cp_err, "Error: improper min/max/avg call.\n");
            }

        }
    }

    switch (mFunctionType)
    {
    case AT_AVG: {
        meas->m_measured = mValue / (first ? Tsum : 1.0);
        meas->m_measured_at = svalue;
        break;
    }
    case AT_MIN:
    case AT_MAX:
    case AT_MIN_AT:
    case AT_MAX_AT: {
        meas->m_measured = mValue;
        meas->m_measured_at = mValueAt;
        break;
    }
    default :
        fprintf(cp_err, "Error: improper min/max/avg call.\n");
    }
}


/* -----------------------------------------------------------------
 * Function: process an RMS or INTEG statement which has been
 * parsed into a measurement structure.  Here we do interpolate
 * the starting and stopping time window so the answer is correct.
 * ----------------------------------------------------------------- */
static void
measure_rms_integral(
    MEASUREPTR meas,              /* in : parsed measurement data request */
    ANALYSIS_TYPE_T mFunctionType /* in: one of AT_RMS, or AT_INTEG */
    )
{
    int i;                      /* counter */
    int xy_size;                /* # of temp array elements */
    struct dvec *d, *xScale;    /* value and indpendent (x-axis) vectors */
    double value, xvalue;       /* current value and independent value */
    double *x;                  /* temp x array */
    double *y;                  /* temp y array */
    double toVal;               /* to time value */
    double *width;              /* temp width array */
    double sum1;                /* first sum */
    double sum2;                /* second sum */
    double sum3;                /* third sum */
    int first;
    bool ac_check = FALSE, sp_check = FALSE, dc_check = FALSE, tran_check = FALSE;

    xvalue = 0;
    meas->m_measured = NAN;
    meas->m_measured_at = NAN;
    first = 0;

    if (cieq (meas->m_analysis, "ac"))
        ac_check = TRUE;
    else if (cieq (meas->m_analysis, "sp"))
        sp_check = TRUE;
    else if (cieq (meas->m_analysis, "dc"))
        dc_check = TRUE;
    else
        tran_check = TRUE;

    d = vec_get(meas->m_vec);
    if (d == NULL) {
        fprintf(cp_err, "Error: no such vector as %s.\n", meas->m_vec);
        return;
    }

    if (ac_check || sp_check) {
        xScale = vec_get("frequency");
    } else if (tran_check) {
        xScale = vec_get("time");
    } else if (dc_check) {
        xScale = vec_get("v-sweep");
    } else {                      /* error */
        fprintf(cp_err, "Error: no such analysis type as %s.\n", meas->m_analysis);
        return;
    }

    if (xScale == NULL) {
        fprintf(cp_err, "Error: no such vector as time.\n");
        return;
    }

    /* Allocate buffers for calculation. */
    x     = TMALLOC(double, xScale->v_length);
    y     = TMALLOC(double, xScale->v_length);
    width = TMALLOC(double, xScale->v_length + 1);

    xy_size = 0;
    toVal = -1;
    /* create new set of values over interval [from, to] -- interpolate if necessary */
    for (i = 0; i < d->v_length; i++) {
        if (ac_check) {
            if (d->v_compdata) {
                value = get_value(meas, d, i); //d->v_compdata[i].cx_real;
            } else {
                value = d->v_realdata[i];
                // fprintf(cp_err, "Warning: 'meas ac' input vector is real!\n");
            }
            xvalue = xScale->v_compdata[i].cx_real;
        } else {
            value = d->v_realdata[i];
            xvalue = xScale->v_realdata[i];
        }

        if (xvalue < meas->m_from)
            continue;

        if ((meas->m_to != 0.0e0) && (xvalue > meas->m_to)) {
            // interpolate ending value if necessary.
            if (!AlmostEqualUlps(xvalue, meas->m_to, 100)) {
                value = measure_interpolate(xScale, d, i-1, i, meas->m_to, 'y', meas);
                xvalue = meas->m_to;
            }
            x[xy_size] = xvalue;
            if (mFunctionType == AT_RMS)
                y[xy_size++] = value * value;
            else
                y[xy_size++] = value;
            toVal = xvalue;
            break;
        }

        if (first == 0) {
            if (meas->m_from != 0.0e0 && (i > 0)) {
                // interpolate starting value.
                if (!AlmostEqualUlps(xvalue, meas->m_from, 100)) {
                    value = measure_interpolate(xScale, d, i-1, i, meas->m_from, 'y' , meas);
                    xvalue = meas->m_from;
                }
            }
            meas->m_measured_at = xvalue;
            first = 1;
        }
        x[xy_size] = xvalue;
        if (mFunctionType == AT_RMS)
            y[xy_size++] = value * value;
        else
            y[xy_size++] = value;
    }

    // evaluate segment width
    for (i = 0; i < xy_size-1; i++)
        width[i] = x[i+1] - x[i];
    width[i++] = 0;
    width[i++] = 0;

    // Compute Integral (area under curve)
    i = 0;
    sum1 = sum2 = sum3 = 0.0;
    while (i < xy_size-1) {
        // Simpson's 3/8 Rule
        if (AlmostEqualUlps(width[i], width[i+1], 100) &&
            AlmostEqualUlps(width[i], width[i+2], 100)) {
            sum1 += 3*width[i] * (y[i] + 3*(y[i+1] + y[i+2]) + y[i+3]) / 8.0;
            i += 3;
        }
        // Simpson's 1/3 Rule
        else if (AlmostEqualUlps(width[i], width[i+1], 100)) {
            sum2 += width[i] * (y[i] + 4*y[i+1] + y[i+2]) / 3.0;
            i += 2;
        }
        // Trapezoidal Rule
        else if (!AlmostEqualUlps(width[i], width[i+1], 100)) {
            sum3 += width[i] * (y[i] + y[i+1]) / 2;
            i++;
        }
    }

    /* Now set the measurement values if not set */
    if (toVal < 0.0) {
        if (ac_check) {
            if (d->v_compdata) {
                value = get_value(meas, d, i); //d->v_compdata[i].cx_real;
            } else {
                value = d->v_realdata[i];
                // fprintf(cp_err, "Warning: 'meas ac' input vector is real!\n");
            }
            xvalue = xScale->v_compdata[i].cx_real;
            toVal = xScale->v_compdata[d->v_length-1].cx_real;
        } else {
            toVal = xScale->v_realdata[d->v_length-1];
        }


    }
    meas->m_from = meas->m_measured_at;
    meas->m_to = toVal;

    if (mFunctionType == AT_RMS) {
        meas->m_measured = (sum1 + sum2 + sum3)/ (toVal - meas->m_measured_at);
        meas->m_measured = sqrt(meas->m_measured);

    } else {
        meas->m_measured = (sum1 + sum2 + sum3);
    }

    txfree(x);
    txfree(y);
    txfree(width);
}


/* -----------------------------------------------------------------
 * Function: Wrapper function to process a RMS measurement.
 * ----------------------------------------------------------------- */
#if 0
static void
measure_rms(
    MEASUREPTR meas             /* in : parsed measurement data request */
    )
{
    // RMS (root mean squared):
    // Calculates the square root of the area under the 'out_var2' curve
    //  divided be the period of interest
    measure_rms_integral(meas, AT_RMS);
}
#endif


/* -----------------------------------------------------------------
 * Function: Wrapper function to process a integration measurement.
 * ----------------------------------------------------------------- */
#if 0
static void
measure_integ(
    MEASUREPTR meas             /* in : parsed measurement data request */
    )
{
    // INTEGRAL INTEG
    measure_rms_integral(meas, AT_INTEG);
}
#endif


/* still some more work to do.... */
#if 0
static void
measure_deriv(void)
{
    // DERIVATIVE DERIV
}
#endif


// ERR Equations
#if 0
static void
measure_ERR(void)
{
}

static void
measure_ERR1(void)
{
}

static void
measure_ERR2(void)
{
}

static void
measure_ERR3(void)
{
}
#endif


void
com_dotmeasure(wordlist *wl)
{
    NG_IGNORE(wl);

    /* simulation info */
    // printf("*%s\n", plot_cur->pl_title);
    // printf("\t %s, %s\n", plot_cur->pl_name, plot_cur->pl_date); // missing temp
}


/* -----------------------------------------------------------------
 * Function: Given a measurement variable name, see if the analysis
 * has generated a measure vector for it.  Returns TRUE if it exists
 * or varname is NULL,  Return FALSE otherwise
 * ----------------------------------------------------------------- */
static int
measure_valid_vector(
    char *varname               /* in: requested variable name */
    )
{
    struct dvec *d;             /* measurement vector */

    if (varname == NULL)
        return TRUE;

    d = vec_get(varname);
    if (d == NULL)
        return FALSE;

    return TRUE;
}


/* -----------------------------------------------------------------
 * Function: Given a wordlist and measurement structure, parse the
 * standard parameters such as RISE, FALL, VAL, TD, FROM, TO, etc.
 * in a measurement statement.   We also check the appropriate
 * variables found in the measurement statement.
 * ----------------------------------------------------------------- */
static int
measure_parse_stdParams(
    MEASUREPTR meas,          /* in : measurement structure */
    wordlist *wl,             /* in : word list to parse */
    wordlist *wlBreak,        /* out: where we stopped parsing */
    char *errbuf              /* in/out: buffer where we write error messages */
    )
{
    int pCnt;
    char *p, *pName, *pValue;
    double *engVal, engVal1;

    pCnt = 0;
    while (wl != wlBreak) {
        p = wl->wl_word;
        pName = strtok(p, "=");
        pValue = strtok(NULL, "=");

        if (pValue == NULL) {
            if (strcasecmp(pName, "LAST") == 0) {
                meas->m_cross = MEASURE_LAST_TRANSITION;
                meas->m_rise = -1;
                meas->m_fall = -1;
                pCnt ++;
                wl = wl->wl_next;
                continue;
            } else {
                sprintf(errbuf, "bad syntax of ??\n");
                return 0;
            }
        }

        if (strcasecmp(pValue, "LAST") == 0) {
            engVal1 = MEASURE_LAST_TRANSITION;
        } else {
            if ((engVal = ft_numparse(&pValue, FALSE)) == NULL) {
                sprintf(errbuf, "bad syntax of ??\n");
                return 0;
            }
            engVal1 = *engVal;  // What is this ??
        }

        if (strcasecmp(pName, "RISE") == 0) {
            meas->m_rise = (int)floor(engVal1 + 0.5);
            meas->m_fall = -1;
            meas->m_cross = -1;
        } else if (strcasecmp(pName, "FALL") == 0) {
            meas->m_fall = (int)floor(engVal1 + 0.5);
            meas->m_rise = -1;
            meas->m_cross = -1;
        } else if (strcasecmp(pName, "CROSS") == 0) {
            meas->m_cross = (int)floor(engVal1 + 0.5);
            meas->m_rise = -1;
            meas->m_fall = -1;
        } else if (strcasecmp(pName, "VAL") == 0) {
            meas->m_val = engVal1;
        } else if (strcasecmp(pName, "TD") == 0) {
            meas->m_td = engVal1;
        } else if (strcasecmp(pName, "FROM") == 0) {
            meas->m_from = engVal1;
        } else if (strcasecmp(pName, "TO") == 0) {
            meas->m_to = engVal1;
        } else if (strcasecmp(pName, "AT") == 0) {
            meas->m_at = engVal1;
        } else {
            sprintf(errbuf, "no such parameter as '%s'\n", pName);
            return 0;
        }

        pCnt ++;
        wl = wl->wl_next;
    }

    if (pCnt == 0) {
        sprintf(errbuf, "bad syntax of ??\n");
        return 0;
    }

    // valid vector
    if (measure_valid_vector(meas->m_vec) == 0) {
        sprintf(errbuf, "no such vector as '%s'\n", meas->m_vec);
        return 0;
    }

    // valid vector2
    if (meas->m_vec2 != NULL)
        if (measure_valid_vector(meas->m_vec2) == 0) {
            sprintf(errbuf, "no such vector as '%s'\n", meas->m_vec2);
            return 0;
        }

    /* dc: make m_from always less than m_to */
    if (cieq("dc", meas->m_analysis))
        if (meas->m_to < meas->m_from) {
            SWAP(double, meas->m_from, meas->m_to);
        }

    return 1;
}


/* -----------------------------------------------------------------
 * Function: Given a wordlist and measurement structure, parse a
 * FIND measurement statement.   Most of the work is done by calling
 * measure_parse_stdParams.
 * ----------------------------------------------------------------- */
static int
measure_parse_find(
    MEASUREPTR meas,          /* in : measurement structure */
    wordlist *wl,             /* in : word list to parse */
    wordlist *wlBreak,        /* out: where we stopped parsing */
    char *errbuf              /* in/out: buffer where we write error messages */
    )
{
    int pCnt;
    char *p, *pName, *pVal;
    double *engVal, engVal1;

    meas->m_vec = NULL;
    meas->m_vec2 = NULL;
    meas->m_val = 1e99;
    meas->m_cross = -1;
    meas->m_fall = -1;
    meas->m_rise = -1;
    meas->m_td = 0;
    meas->m_from = 0.0e0;
    meas->m_to = 0.0e0;
    meas->m_at = 1e99;

    /* for DC, set new outer limits for 'from' and 'to'
       because 0.0e0 may be valid inside of range */
    if (cieq("dc", meas->m_analysis)) {
        meas->m_to = 1.0e99;
        meas->m_from = -1.0e99;
    }

    pCnt = 0;
    while (wl != wlBreak) {
        p = wl->wl_word;

        if (pCnt == 0) {
            meas->m_vec = cp_unquote(wl->wl_word);
            /* correct for vectors like vm, vp etc. */
            if (cieq("ac", meas->m_analysis) || cieq("sp", meas->m_analysis))
                correct_vec(meas);
        } else if (pCnt == 1) {
            pName = strtok(p, "=");
            pVal = strtok(NULL, "=");

            if (pVal == NULL) {
                sprintf(errbuf, "bad syntax of WHEN\n");
                return 0;
            }

            if (strcasecmp(pName, "AT") == 0) {
                if ((engVal = ft_numparse(&pVal, FALSE)) == NULL) {
                    sprintf(errbuf, "bad syntax of WHEN\n");
                    return 0;
                }

                engVal1 = *engVal;

                meas->m_at = engVal1;

            } else {
                sprintf(errbuf, "bad syntax of WHEN\n");
                return 0;
            }
        } else {
            if (measure_parse_stdParams(meas, wl, NULL, errbuf) == 0)
                return 0;
        }

        wl = wl->wl_next;
        pCnt ++;
    }

    return 1;
}


/* -----------------------------------------------------------------
 * Function: Given a wordlist and measurement structure, parse a
 * WHEN measurement statement.   Most of the work is done by calling
 * measure_parse_stdParams.
 * ----------------------------------------------------------------- */
static int
measure_parse_when(
    MEASUREPTR meas,          /* in : measurement structure */
    wordlist *wl,             /* in : word list to parse */
    char *errBuf              /* in/out: buffer where we write error messages */
    )
{
    int pCnt, err = 0;
    char *p, *pVar1, *pVar2;
    meas->m_vec = NULL;
    meas->m_vec2 = NULL;
    meas->m_val = 1e99;
    meas->m_cross = -1;
    meas->m_fall = -1;
    meas->m_rise = -1;
    meas->m_td = 0;
    meas->m_from = 0.0e0;
    meas->m_to = 0.0e0;
    meas->m_at = 1e99;


    /* for DC, set new outer limits for 'from' and 'to'
       because 0.0e0 may be valid inside of range */
    if (cieq("dc", meas->m_analysis)) {
        meas->m_to = 1.0e99;
        meas->m_from = -1.0e99;
    }

    pCnt = 0;
    while (wl) {
        p = wl->wl_word;

        if (pCnt == 0) {
            pVar1 = strtok(p, "=");
            pVar2 = strtok(NULL, "=");

            if (pVar2 == NULL) {
                sprintf(errBuf, "bad syntax\n");
                return 0;
            }

            meas->m_vec = copy(pVar1);
            /* correct for vectors like vm, vp etc. */
            if (cieq("ac", meas->m_analysis) || cieq("sp", meas->m_analysis))
                correct_vec(meas);
            if (measure_valid_vector(pVar2) == 1) {
                meas->m_vec2 = copy(pVar2);
                /* correct for vectors like vm, vp etc. */
                if (cieq("ac", meas->m_analysis) || cieq("sp", meas->m_analysis))
                    correct_vec(meas);
            } else {
                meas->m_val = INPevaluate(&pVar2, &err, 1);
            }
        } else {
            if (measure_parse_stdParams(meas, wl, NULL, errBuf) == 0)
                return 0;
            break;
        }

        wl = wl->wl_next;
        pCnt ++;
    }
    return 1;
}


/* -----------------------------------------------------------------
 * Function: Given a wordlist and measurement structure, parse a
 * TRIGGER or TARGET clause of a measurement statement.   Most of the
 * work is done by calling measure_parse_stdParams.
 * ----------------------------------------------------------------- */
static int
measure_parse_trigtarg(
    MEASUREPTR meas,          /* in : measurement structure */
    wordlist *words,          /* in : word list to parse */
    wordlist *wlTarg,         /* out : where we stopped parsing target clause */
    char *trigTarg,           /* in : type of clause */
    char *errbuf              /* in/out: buffer where we write error messages */
    )
{
    int pcnt;
    char *p;

    meas->m_vec = NULL;
    meas->m_vec2 = NULL;
    meas->m_cross = -1;
    meas->m_fall = -1;
    meas->m_rise = -1;
    meas->m_td = 0;
    meas->m_from = 0.0e0;
    meas->m_to = 0.0e0;
    meas->m_at = 1e99;

    /* for DC, set new outer limits for 'from' and 'to'
       because 0.0e0 may be valid inside of range */
    if (cieq("dc", meas->m_analysis)) {
        meas->m_to = 1.0e99;
        meas->m_from = -1.0e99;
    }

    pcnt = 0;

    while (words != wlTarg) {
        p = words->wl_word;

        if ((pcnt == 0) && !ciprefix("at", p)) {
            meas->m_vec = cp_unquote(words->wl_word);
            /* correct for vectors like vm, vp etc. */
            if (cieq("ac", meas->m_analysis) || cieq("sp", meas->m_analysis))
                correct_vec(meas);
        } else if (ciprefix("at", p)) {
            if (measure_parse_stdParams(meas, words, wlTarg, errbuf) == 0)
                return 0;
        } else {
            if (measure_parse_stdParams(meas, words, wlTarg, errbuf) == 0)
                return 0;
            break;
        }

        words = words->wl_next;
        pcnt ++;
    }

    if (pcnt == 0) {
        sprintf(errbuf, "bad syntax of '%s'\n", trigTarg);
        return 0;
    }

    // valid vector
    if (measure_valid_vector(meas->m_vec) == 0) {
        sprintf(errbuf, "no such vector as '%s'\n", meas->m_vec);
        return 0;
    }

    return 1;
}


/* -----------------------------------------------------------------
 * Function: Given a wordlist, extract the measurement statement,
 * process it, and return a result.  If out_line is furnished, we
 * format and copy the result it this string buffer.  The autocheck
 * variable allows us to check for "autostop".  This function is
 * called from measure.c.    We use the functions in this file because
 * the parsing is much more complete and thorough.
 * ----------------------------------------------------------------- */
int
get_measure2(
    wordlist *wl,     /* in: a word list for us to process */
    double *result,   /* out : the result of the measurement */
    char *out_line,   /* out: formatted result - may be NULL */
    bool autocheck    /* in: TRUE if checking for "autostop"; FALSE otherwise */
    )
{
    wordlist *words, *wlTarg, *wlWhen;
    char errbuf[100];
    char *mAnalysis = NULL;     // analysis type
    char *mName = NULL;         // name given to the measured output
    char *mFunction = "";
    int precision;              // measurement precision
    ANALYSIS_TYPE_T mFunctionType = AT_UNKNOWN;
    int wl_cnt;
    char *p;
    int ret_val = MEASUREMENT_FAILURE;

    *result = 0.0e0;        /* default result */

    if (!wl) {
        printf("usage: measure .....\n");
        return MEASUREMENT_FAILURE;
    }

    if (!plot_cur || !plot_cur->pl_dvecs || !plot_cur->pl_scale) {
        fprintf(cp_err, "Error: no vectors available\n");
        return MEASUREMENT_FAILURE;
    }

    if (!ciprefix("tran", plot_cur->pl_typename) &&
        !ciprefix("ac", plot_cur->pl_typename) &&
        !ciprefix("dc", plot_cur->pl_typename) &&
        !ciprefix("sp", plot_cur->pl_typename))
    {
        fprintf(cp_err, "Error: measure limited to tran, dc, sp, or ac analysis\n");
        return MEASUREMENT_FAILURE;
    }

    words = wl;
    wlTarg = NULL;
    wlWhen = NULL;

    if (!words) {
        fprintf(cp_err, "Error: no assignment found.\n");
        return MEASUREMENT_FAILURE;
    }

    precision = measure_get_precision();
    wl_cnt = 0;
    while (words) {

        switch (wl_cnt)
        {
        case 0:
            mAnalysis = cp_unquote(words->wl_word);
            break;
        case 1:
            mName = cp_unquote(words->wl_word);
            break;
        case 2:
        {
            mFunctionType = measure_function_type(words->wl_word);
            if (mFunctionType == AT_UNKNOWN) {
                if (!autocheck) {
                    printf("\tmeasure '%s'  failed\n", mName);
                    printf("Error: measure  %s  :\n", mName);
                    printf("\tno such function as '%s'\n", words->wl_word);
                }
                return MEASUREMENT_FAILURE;
            }
            break;
        }
        default:
        {
            p = words->wl_word;

            if (strcasecmp(p, "targ") == 0)
                wlTarg = words;

            if (strcasecmp(p, "when") == 0)
                wlWhen = words;

            break;
        }
        }
        wl_cnt ++;
        words = words->wl_next;
    }

    if (wl_cnt < 3) {
        printf("\tmeasure '%s'  failed\n", mName);
        printf("Error: measure  %s  :\n", mName);
        printf("\tinvalid num params\n");
        return MEASUREMENT_FAILURE;
    }

    //------------------------


    words = wl;

    if (words)
        words = words->wl_next; // skip
    if (words)
        words = words->wl_next; // skip results name
    if (words)
        words = words->wl_next; // Function

    // switch here
    switch (mFunctionType)
    {
    case AT_DELAY:
    case AT_TRIG:
    {
        // trig parameters
        MEASUREPTR measTrig, measTarg;
        measTrig = TMALLOC(struct measure, 1);
        measTarg = TMALLOC(struct measure, 1);

        measTrig->m_analysis = measTarg->m_analysis = mAnalysis;

        if (measure_parse_trigtarg(measTrig, words , wlTarg, "trig", errbuf) == 0) {
            measure_errMessage(mName, mFunction, "TRIG", errbuf, autocheck);
            goto err_ret1;
        }

        if ((measTrig->m_rise == -1) && (measTrig->m_fall == -1) &&
            (measTrig->m_cross == -1) && (measTrig->m_at == 1e99)) {
            sprintf(errbuf, "at, rise, fall or cross must be given\n");
            measure_errMessage(mName, mFunction, "TRIG", errbuf, autocheck);
            goto err_ret1;
        }

        while (words != wlTarg)
            words = words->wl_next; // hack

        if (words)
            words = words->wl_next; // skip targ

        if (measure_parse_trigtarg(measTarg, words , NULL, "targ", errbuf) == 0) {
            measure_errMessage(mName, mFunction, "TARG", errbuf, autocheck);
            goto err_ret1;
        }

        if ((measTarg->m_rise == -1) && (measTarg->m_fall == -1) &&
            (measTarg->m_cross == -1)&& (measTarg->m_at == 1e99)) {
            sprintf(errbuf, "at, rise, fall or cross must be given\n");
            measure_errMessage(mName, mFunction, "TARG", errbuf, autocheck);
            goto err_ret1;
        }

        // measure trig
        if (measTrig->m_at == 1e99)
            com_measure_when(measTrig);
        else
            measTrig->m_measured = measTrig->m_at;


        if (isnan(measTrig->m_measured)) {
            sprintf(errbuf, "out of interval\n");
            measure_errMessage(mName, mFunction, "TRIG", errbuf, autocheck);
            goto err_ret1;
        }
        // measure targ
        com_measure_when(measTarg);

        if (isnan(measTarg->m_measured)) {
            sprintf(errbuf, "out of interval\n");
            measure_errMessage(mName, mFunction, "TARG", errbuf, autocheck);
            goto err_ret1;
        }

        // print results
        if (out_line)
            sprintf(out_line, "%-20s=  %e targ=  %e trig=  %e\n", mName, (measTarg->m_measured - measTrig->m_measured), measTarg->m_measured, measTrig->m_measured);
        else
            printf("%-20s=  %e targ=  %e trig=  %e\n", mName, (measTarg->m_measured - measTrig->m_measured), measTarg->m_measured, measTrig->m_measured);

        *result = (measTarg->m_measured - measTrig->m_measured);

        ret_val = MEASUREMENT_OK;

err_ret1:
        tfree(mAnalysis);
        tfree(mName);
        tfree(measTarg->m_vec);
        tfree(measTarg);
        tfree(measTrig->m_vec);
        tfree(measTrig);

        return ret_val;
    }
    case AT_FIND:
    {
        MEASUREPTR meas, measFind;
        meas = TMALLOC(struct measure, 1);
        measFind = TMALLOC(struct measure, 1);

        meas->m_analysis = measFind->m_analysis = mAnalysis;

        if (measure_parse_find(meas, words, wlWhen, errbuf) == 0) {
            measure_errMessage(mName, mFunction, "FIND", errbuf, autocheck);
            goto err_ret2;
        }

        if (meas->m_at == 1e99) {
            // find .. when statment
            while (words != wlWhen)
                words = words->wl_next; // hack

            if (words)
                words = words->wl_next; // skip targ

            if (measure_parse_when(measFind, words, errbuf) == 0) {
                measure_errMessage(mName, mFunction, "WHEN", errbuf, autocheck);
                goto err_ret2;
            }

            com_measure_when(measFind);

            if (isnan(measFind->m_measured)) {
                sprintf(errbuf, "out of interval\n");
                measure_errMessage(mName, mFunction, "AT", errbuf, autocheck);
                goto err_ret2;
            }

            measure_at(meas, measFind->m_measured);
            meas->m_at = measFind->m_measured;

        } else {
            measure_at(meas, meas->m_at);
        }

        if (isnan(meas->m_measured)) {
            sprintf(errbuf, "out of interval\n");
            measure_errMessage(mName, mFunction, "AT", errbuf, autocheck);
            goto err_ret2;
        }

        // print results
        if (out_line)
            sprintf(out_line, "%-20s=  %e\n", mName, meas->m_measured);
        else
            printf("%-20s=  %e\n", mName, meas->m_measured);

        *result = meas->m_measured;

        ret_val = MEASUREMENT_OK;

err_ret2:
        tfree(mAnalysis);
        tfree(mName);
        tfree(meas->m_vec);
        tfree(meas);
        tfree(measFind->m_vec);
        tfree(measFind);

        return ret_val;
    }
    case AT_WHEN:
    {
        MEASUREPTR meas;
        meas = TMALLOC(struct measure, 1);
        meas->m_analysis = mAnalysis;
        if (measure_parse_when(meas, words, errbuf) == 0) {
            measure_errMessage(mName, mFunction, "WHEN", errbuf, autocheck);
            goto err_ret3;
        }

        com_measure_when(meas);

        if (isnan(meas->m_measured)) {
            sprintf(errbuf, "out of interval\n");
            measure_errMessage(mName, mFunction, "WHEN", errbuf, autocheck);
            goto err_ret3;
        }

        // print results
        if (out_line)
            sprintf(out_line, "%-20s=   %.*e\n", mName, precision, meas->m_measured);
        else
            printf("%-20s=  %e\n", mName, meas->m_measured);

        *result = meas->m_measured;

        ret_val = MEASUREMENT_OK;

err_ret3:
        tfree(mAnalysis);
        tfree(mName);
        tfree(meas->m_vec);
        tfree(meas);

        return ret_val;
    }
    case AT_RMS:
    case AT_INTEG:
    {
        // trig parameters
        MEASUREPTR meas;
        meas = TMALLOC(struct measure, 1);
        meas->m_analysis = mAnalysis;
        if (measure_parse_trigtarg(meas, words , NULL, "trig", errbuf) == 0) {
            measure_errMessage(mName, mFunction, "TRIG", errbuf, autocheck);
            goto err_ret4;
        }

        // measure
        measure_rms_integral(meas, mFunctionType);

        if (isnan(meas->m_measured)) {
            sprintf(errbuf, "out of interval\n");
            measure_errMessage(mName, mFunction, "TRIG", errbuf, autocheck); // ??
            goto err_ret4;
        }

        if (meas->m_at == 1e99)
            meas->m_at = 0.0e0;

        // print results
        if (out_line)
            sprintf(out_line, "%-20s=   %.*e from=  %.*e to=  %.*e\n", mName, precision, meas->m_measured, precision, meas->m_from, precision, meas->m_to);
        else
            printf("%-20s=  %.*e from=  %.*e to=  %.*e\n", mName, precision, meas->m_measured, precision, meas->m_from, precision, meas->m_to);

        *result = meas->m_measured;

        ret_val = MEASUREMENT_OK;

err_ret4:
        tfree(mAnalysis);
        tfree(mName);
        tfree(meas->m_vec);
        tfree(meas);

        return ret_val;

    }
    case AT_AVG:
    {
        // trig parameters
        MEASUREPTR meas;
        meas = TMALLOC(struct measure, 1);

        meas->m_analysis = mAnalysis;

        if (measure_parse_trigtarg(meas, words , NULL, "trig", errbuf) == 0) {
            measure_errMessage(mName, mFunction, "TRIG", errbuf, autocheck);
            goto err_ret5;
        }

        // measure
        measure_minMaxAvg(meas, mFunctionType);
        if (isnan(meas->m_measured)) {
            sprintf(errbuf, "out of interval\n");
            measure_errMessage(mName, mFunction, "TRIG", errbuf, autocheck); // ??
            goto err_ret5;
        }

        if (meas->m_at == 1e99)
            meas->m_at = meas->m_from;

        // print results
        if (out_line)
            sprintf(out_line, "%-20s=  %e from=  %e to=  %e\n", mName, meas->m_measured, meas->m_at, meas->m_measured_at);
        else
            printf("%-20s=  %e from=  %e to=  %e\n", mName, meas->m_measured, meas->m_at, meas->m_measured_at);

        *result = meas->m_measured;

        ret_val = MEASUREMENT_OK;

err_ret5:
        tfree(mAnalysis);
        tfree(mName);
        tfree(meas->m_vec);
        tfree(meas);

        return ret_val;
    }
    case AT_MIN:
    case AT_MAX:
    case AT_MIN_AT:
    case AT_MAX_AT:
    {
        // trig parameters
        MEASUREPTR measTrig;
        measTrig = TMALLOC(struct measure, 1);
        measTrig->m_analysis = mAnalysis;
        if (measure_parse_trigtarg(measTrig, words , NULL, "trig", errbuf) == 0) {
            measure_errMessage(mName, mFunction, "TRIG", errbuf, autocheck);
            goto err_ret6;
        }

        // measure
        if ((mFunctionType == AT_MIN) || (mFunctionType == AT_MIN_AT))
            measure_minMaxAvg(measTrig, AT_MIN);
        else
            measure_minMaxAvg(measTrig, AT_MAX);

        if (isnan(measTrig->m_measured)) {
            sprintf(errbuf, "out of interval\n");
            measure_errMessage(mName, mFunction, "TRIG", errbuf, autocheck); // ??
            goto err_ret6;
        }

        if ((mFunctionType == AT_MIN) || (mFunctionType == AT_MAX)) {
            // print results
            if (out_line)
                sprintf(out_line, "%-20s=  %e at=  %e\n", mName, measTrig->m_measured, measTrig->m_measured_at);
            else
                printf("%-20s=  %e at=  %e\n", mName, measTrig->m_measured, measTrig->m_measured_at);

            *result = measTrig->m_measured;
        } else {
            // print results
            if (out_line)
                sprintf(out_line, "%-20s=  %e with=  %e\n", mName, measTrig->m_measured_at, measTrig->m_measured);
            else
                printf("%-20s=  %e with=  %e\n", mName, measTrig->m_measured_at, measTrig->m_measured);

            *result = measTrig->m_measured_at;
        }

        ret_val = MEASUREMENT_OK;

err_ret6:
        tfree(mAnalysis);
        tfree(mName);
        tfree(measTrig->m_vec);
        tfree(measTrig);

        return ret_val;
    }
    case AT_PP:
    {
        double minValue, maxValue;
        MEASUREPTR measTrig;
        measTrig = TMALLOC(struct measure, 1);
        measTrig->m_analysis = mAnalysis;
        if (measure_parse_trigtarg(measTrig, words , NULL, "trig", errbuf) == 0) {
            measure_errMessage(mName, mFunction, "TRIG", errbuf, autocheck);
            goto err_ret7;
        }

        // measure min
        measure_minMaxAvg(measTrig, AT_MIN);
        if (isnan(measTrig->m_measured)) {
            sprintf(errbuf, "out of interval\n");
            measure_errMessage(mName, mFunction, "TRIG", errbuf, autocheck); // ??
            goto err_ret7;
        }
        minValue = measTrig->m_measured;

        // measure max
        measure_minMaxAvg(measTrig, AT_MAX);
        if (isnan(measTrig->m_measured)) {
            sprintf(errbuf, "out of interval\n");
            measure_errMessage(mName, mFunction, "TRIG", errbuf, autocheck); // ??
            goto err_ret7;
        }
        maxValue = measTrig->m_measured;

        // print results
        if (out_line)
            sprintf(out_line, "%-20s=  %e from=  %e to=  %e\n", mName, (maxValue - minValue), measTrig->m_from, measTrig->m_to);
        else
            printf("%-20s=  %e from=  %e to=  %e\n", mName, (maxValue - minValue), measTrig->m_from, measTrig->m_to);

        *result = (maxValue - minValue);

        ret_val = MEASUREMENT_OK;

err_ret7:
        tfree(mAnalysis);
        tfree(mName);
        tfree(measTrig->m_vec);
        tfree(measTrig);

        return ret_val;
    }

    case AT_DERIV:
    case AT_ERR:
    case AT_ERR1:
    case AT_ERR2:
    case AT_ERR3:
    {
        printf("\tmeasure '%s'  failed\n", mName);
        printf("Error: measure  %s  :\n", mName);
        printf("\tfunction '%s' currently not supported\n", mFunction);
        break;
    }

    default:
    {
        fprintf(stderr, "ERROR: enumeration value `AT_UNKNOWN' not handled in get_measure2\nAborting...\n");
        controlled_exit(EXIT_FAILURE);
    }
    }

    return MEASUREMENT_FAILURE;
}