luke
/
ngspice
mirror of https://git.code.sf.net/p/ngspice/ngspice
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Merge branch 'pre-master-46' of ssh://git.code.sf.net/p/ngspice/ngspice into pre-master-46 

Aknowledge external merger
This commit is contained in:
Holger Vogt 2026-02-28 17:27:43 +01:00
parent 3103be7eea 04507a637d
commit e53291ad2b
1 changed files with 21 additions and 15 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

36
src/frontend/fourier.c
View File

@ -23,7 +23,7 @@ Author: 1985 Wayne A. Christopher, U. C. Berkeley CAD Group
static char *pnum(double num);
static int CKTfour(int ndata, int numFreq, double *thd, double *Time, double *Value,
static int CKTfour(int ndata, int numFreq, int numPeriod, double *thd, double *Time, double *Value,
double FundFreq, double *Freq, double *Mag, double *Phase, double *nMag,
double *nPhase);
@ -32,8 +32,8 @@ static int CKTfour(int ndata, int numFreq, double *thd, double *Time, double *Va
#define DEF_FOURGRIDSIZE 200
/* CKTfour(ndata, numFreq, thd, Time, Value, FundFreq, Freq, Mag, Phase, nMag, nPhase)
* len 10 ? inp inp inp out out out out out
/* CKTfour(ndata, numFreq, numPeriod, thd, Time, Value, FundFreq, Freq, Mag, Phase, nMag, nPhase)
* len 10 1 ? inp inp inp out out out out out
*/
int
@ -42,7 +42,7 @@ fourier(wordlist *wl, struct plot *current_plot)
struct dvec *time, *vec;
struct pnode *pn, *names;
double fundfreq, *data = NULL;
int nfreqs, fourgridsize, polydegree;
int nfreqs, nperiods, fourgridsize, polydegree;
double *freq, *mag, *phase, *nmag, *nphase; /* Outputs from CKTfour */
double thd, *timescale = NULL;
char *s;
@ -68,6 +68,8 @@ fourier(wordlist *wl, struct plot *current_plot)
if (!cp_getvar("nfreqs", CP_NUM, &nfreqs, 0) || nfreqs < 1)
nfreqs = 10;
if (!cp_getvar("nperiods", CP_NUM, &nperiods, 0) || nperiods < 1)
nperiods = 1;
if (!cp_getvar("polydegree", CP_NUM, &polydegree, 0) || polydegree < 0)
polydegree = 1;
if (!cp_getvar("fourgridsize", CP_NUM, &fourgridsize, 0) || fourgridsize < 1)
@ -112,14 +114,16 @@ fourier(wordlist *wl, struct plot *current_plot)
if (polydegree) {
double *dp, d;
/* Get fourgridsize points per period */
fourgridsize = fourgridsize * nperiods;
/* Build the grid... */
timescale = TMALLOC(double, fourgridsize);
data = TMALLOC(double, fourgridsize);
dp = ft_minmax(time, TRUE);
/* Now get the last fund freq... */
d = 1 / fundfreq; /* The wavelength... */
d = nperiods / fundfreq; /* The wavelength... */
if (dp[1] - dp[0] < d) {
fprintf(cp_err, "Error: wavelength longer than time span\n");
fprintf(cp_err, "Error: (%d * wavelength) longer than time span\n", nperiods);
goto done;
} else if (dp[1] - dp[0] > d) {
dp[0] = dp[1] - d;
@ -143,7 +147,7 @@ fourier(wordlist *wl, struct plot *current_plot)
timescale = time->v_realdata;
}
err = CKTfour(fourgridsize, nfreqs, &thd, timescale,
err = CKTfour(fourgridsize, nfreqs, nperiods, &thd, timescale,
data, fundfreq, freq, mag, phase, nmag,
nphase);
if (err != OK) {
@ -153,9 +157,10 @@ fourier(wordlist *wl, struct plot *current_plot)
fprintf(cp_out, "Fourier analysis for %s:\n", vec->v_name);
fprintf(cp_out,
" No. Harmonics: %d, THD: %g %%, Gridsize: %d, Interpolation Degree: %d\n\n",
" No. Harmonics: %d, THD: %g %%, Gridsize: %d, Interpolation Degree: %d,"
" No. Periods: %d\n\n",
nfreqs, thd, fourgridsize,
polydegree);
polydegree, nperiods);
/* Each field will have width cp_numdgt + 6 (or 7
* with HP-UX) + 1 if there is a - sign.
*/
@ -288,6 +293,7 @@ static int
CKTfour(int ndata, /* number of entries in the Time and
Value arrays */
int numFreq, /* number of harmonics to calculate */
int numPeriod, /* number of periods for detection */
double *thd, /* total harmonic distortion (percent)
to be returned */
double *Time, /* times at which the voltage/current
@ -313,10 +319,10 @@ CKTfour(int ndata, /* number of entries in the Time and
* The arrays must all be allocated by the caller.
* The Time and Value array must be reasonably distributed over at
* least one full period of the fundamental Frequency for the
* fourier transform to be useful. The function will take the
* last period of the frequency as data for the transform.
* fourier transform to be useful. The function will take
* numPeriod periods of the frequency as data for the transform.
*
* We are assuming that the caller has provided exactly one period
* We are assuming that the caller has provided exactly numPeriod periods
* of the fundamental frequency. */
int i;
int j;
@ -331,10 +337,10 @@ CKTfour(int ndata, /* number of entries in the Time and
Phase[i] = 0;
}
for (i = 0; i < ndata; i++)
for (i = 0; i < ndata ; i++)
for (j = 0; j < numFreq; j++) {
Mag[j] += Value[i] * sin(j*2.0*M_PI*i/((double)ndata));
Phase[j] += Value[i] * cos(j*2.0*M_PI*i/((double)ndata));
Mag[j] += Value[i] * sin(j*2.0*M_PI*numPeriod*i/((double)ndata));
Phase[j] += Value[i] * cos(j*2.0*M_PI*numPeriod*i/((double)ndata));
}
Mag[0] = Phase[0]/ndata;