ngspice/man/man1/ngnutmeg.1

.\" RCS Info: $Revision$ on $Date$
.\"           $Source$
.\" Copyright (c) 1985 Wayne A. Christopher, U. C. Berkeley CAD Group
.TH NUTMEG 1 "27 April 1987"
.UC 4
.SH NAME
nutmeg \- spice post-processor
.SH SYNOPSIS
\fBnutmeg [ - ] [ -n ] [ -t term ] [ datafile ... ]\fR
.SH DESCRIPTION
.B Nutmeg
is a post processor for \s-2SPICE\s+2 \- it takes the raw 
output file created 
by \fBspice -r\fR
and plots the data on a graphics terminal or a workstation display.
Note that the raw output file is different from the
data that \s-2SPICE\s+2 writes to the standard output.
.PP
Arguments are:
.TP
\fB-\fR
Don't try to load the default data file ("rawspice") if no other files
are given.
.TP
\fB-n\fR (or \fB--no-spiceinit\fR)
Don't try to source the file ".spiceinit" upon startup. Normally \fBnutmeg\fR
tries to find the file in the current directory, and if it is not found then
in the user's home directory.
.TP
\fB-t term\fR (or \fB--term=term\fR)
The program is being run on a terminal with \fImfb\fR name \fBterm\fR.
.TP
\fB-h\fR (or \fB--help\fR)
Display a verbose help on the arguments available to the program.
.TP
\fB-v\fR (or \fB--version\fR)
Display a version number and copyright information of the program.
.PP
Further arguments are taken to be data files in binary or ascii format
(see \fBsconvert\fR(1)) which are loaded into nutmeg. If the file
is in binary format, it may be only partially completed (useful for
examining \s-2SPICE\s+2 ouput before the simulation is finished). One
file may contain any number of data sets from different analyses.
.PP
\fBNutmeg\fR
data is in the form of vectors: time, voltage, etc. Each vector has
a type, and vectors can be operated on and combined algebraicly in
ways consistent with their types. Vectors are normally created when
a data file is read in (see the
.B load
command below), and when the initial datafile is loaded. They can
also be created with the
.B let
command.
.PP
An expression 
is an algebraic
formula involving vectors and scalars (a scalar is a vector of
length 1), and the following operations:
.IP
+, -, *, %, /, ^, and ,.
.PP
% is the modulo operator, and the comma operator has two meanings:
if it is present in the argument list of a user-definable function, it
serves to seperate the arguments. Otherwise, the term \fBx , y\fR is
synonymous with \fBx + j(y)\fR.
.PP
Also available are the logical operations & (and), | (or), ! (not),
and the relational operations <, >, >=, <=, =, and <> (not equal).
If used in an algebraic expression they work like they would in C,
producing values of 0 or 1.  The relational operators have the
following synonyms: 
\fB"gt"\fR is >,
\fB"lt"\fR is <, 
\fB"ge"\fR is >=,
\fB"le"\fR is <=,
\fB"ne"\fR is <>,
\fB"eq"\fR is =,
\fB"and"\fR is &,
\fB"or"\fR is |,
and
\fB"not"\fR is !.
These are useful when < and > might be confused with IO redirection
(which is almost always).
.PP
The following functions are available:
.IP
\fBmag(vector) \-\fR
The magnitude of vector.
.IP
\fBph(vector) \-\fR
The phase of vector.
.IP
\fBj(vector) \-\fR
\fIi\fR (sqrt(-1)) times vector.
.IP
\fBreal(vector) \-\fR
The real component of vector.
.IP
\fBimag(vector) \-\fR
The imaginary part of vector.
.IP
\fBdb(vector) \-\fR
20 * log10(mag(vector)).
.IP
\fBlog(vector) \-\fR
The logarithm (base 10) of the vector.
.IP
\fBln(vector) \-\fR
The natural logarithm (base e) of vector.
.IP
\fBexp(vector) \-\fR
e to the vector power.
.IP
\fBabs(vector) \-\fR
The absolute value of vector.
.IP
\fBsqrt(vector) \-\fR
The square root of vector.
.IP
\fBsin(vector) \-\fR
The sin of vector.
.IP
\fBcos(vector) \-\fR
The cosine of vector.
.IP
\fBtan(vector) \-\fR
The tangent of vector.
.IP
\fBatan(vector) \-\fR
The inverse tangent of vector.
.IP
\fBnorm(vector) \-\fR
The \fBvector\fR normalized to 1 (i.e, the largest magnitude of any component
will be 1).
.IP
\fBrnd(vector) \-\fR
A vector with each component a random integer between 0 and the absolute
value of the vectors's corresponding component.
.IP
\fBmean(vector) \-\fR
The result is a scalar (a length 1 vector) that is the mean of the elements
of \fBvector\fR.
.IP
\fBvector(number) \-\fR
The result is a vector of length \fBnumber\fR, with elements 0, 1, ... 
\fBnumber - 1\fR. If \fBnumber\fR is a vector then just the first element
is taken, and if it isn't an integer then the floor of the magnitude is
used.
.IP
\fBlength(vector) \-\fR
The length of \fBvector\fR.
.IP
\fBinterpolate(plot.vector) \-\fR
The result of interpolating the named vector onto the scale of the current
plot.  This function uses the variable \fBpolydegree\fR to determine
the degree of interpolation.
.PP
A vector may be either the name of a vector already defined, a floating-
point number (a scalar), or a list like \fB[elt1 elt2 ... eltn]\fR, which
is a vector of length n.
A number may be written in any format acceptable to \s-2SPICE\s+2, such
as \fB14.6MEG\fR or \fB-1.231E-4\fR. Note that you can either use
scientific notation or one of the abbreviations like \fIMEG\fR or \fIG\fR,
but not both.  As with \s-2SPICE\s+2, a number may have trailing 
alphabetic characters after it.
.PP
The notation \fBexpr [lower upper]\fR, where \fBlower\fR and \fBupper\fR
are numbers, denotes the range of elements from \fBexpr\fR between
\fBlower\fR and \fBupper\fR.  The notation \fBexpr [num]\fR denotes
the \fBnum\fR'th element of \fBexpr\fR.  If \fBupper\fR
is lower than \fBlower\fR, the order of the elements in the vector
is reversed.  In all other cases, \fB[\fR and \fB]\fR serve to surround
literal vectors as described above.  (You may have to use a lot of
parentheses to make sure that you get what you want.  For instance,
you have to type \fBprint (foo) ([1 2])\fR to print the two vectors.
Otherwise it will be interpreted as a function call or a vector with an
index.)  Note that the expression \fBfoo[10 20][5]\fR will \fInot\fR 
yield the 15th element of \fBfoo\fR, but rather the 5th.  In general only
the last index suffix on an expression will take effect.
.PP
To reference vectors in a plot that is not the
\fIcurrent plot\fR (see the \fBsetplot\fR command, below), the
notation \fBplotname.vecname\fR can be used.
.PP
Either a plotname or a vector name may be the wildcard \fBall\fR.  If the
plotname is \fBall\fR, matching vectors from all plots are specified, and
if the vector name is \fBall\fR, all vectors in the specified plots are
referenced.  Note that you may not use binary operations on expressions
involving wildcards \- it is not obvious what \fBall + all\fR should
denote, for instance.
.PP
Thus some (contrived) examples of expressions are:
.IP
\fBcos(TIME) + db(v(3))\fR
.IP
\fBsin(cos(log([1 2 3 4 5 6 7 8 9 10])))\fR
.IP
\fBTIME * rnd(v(9)) - 15 * cos(vin#branch) ^ [7.9e5 8]\fR
.IP
\fBnot ((ac3.FREQ[32] & tran1.TIME[10]) gt 3)\fR
.PP
.B Nutmeg
commands are as follows:
.TP
\fBplot exprs [ylimit ylo yhi] [xlimit xlo xhi] [xindices xilo xihi]\fR
.ce
\fB[xcompress comp] [xdelta xdel] [ydelta ydel] [xlog] [ylog] [vs xname]\fR
.ce
\fB[xlabel word] [ylabel word] [title word] [samep]\fR
Plot the given
.B exprs
on the screen (if you are on a graphics terminal). The
.B xlimit
and
.B ylimit
arguments determine the high and low x- and y-limits of the axes,
respectively. The
.B xindices
arguments determine what range of points are to be plotted \- everything
between the \fBxilo\fR'th point and the \fBxihi\fR'th point is plotted.
The
.B xcompress
argument specifies that only one out of every \fBcomp\fR points should
be plotted. If an \fBxdelta\fR or a \fBydelta\fR parameter is present,
it specifies the spacing between grid lines on the X- and Y-axis.
These parameter names may be abbreviated to
.B xl,
.B yl,
.B xind,
.B xcomp,
.B xdel,
and
.B ydel
respectively.
The
.B xname
argument is an expression to use as the scale on the x-axis. 
If \fBxlog\fR or \fBylog\fR are present, the X or Y scale respectively
will be logarithmic.
The \fBxlabel\fR and \fBylabel\fR arguments cause the specified
labels to be used for the X and Y axes, respectively.
If \fBsamep\fR is given, the values of the other parameters (other than
\fBxname\fR) from the previous \fBplot, hardcopy,\fR or \fBasciiplot\fR
command will be used unless re-defined on the command line.
Finally, the \fBtitle\fR argument will be used in the place of the plot
name at the bottom of the graph.
.TP
\fBhardcopy file \fIplotargs\fR
Just like \fBplot\fR, except creates a file called
.B file
containing the plot.  The file is an image in \fIplot(5)\fR format,
and can be printed by either the \fBplot(1)\fR program or \fBlpr\fR
with the \fB-g\fR flag.
.TP
\fBasciiplot \fIplotargs\fR
Produce a line printer plot of the vectors.
The plot is sent to the standard
output, so you can put it into a file with \fIasciiplot args ... > file\fR.
The \fBset\fR options \fBwidth, height,\fR and \fBnobreak\fR determine
the width and height of the plot, and whether there are page breaks,
respectively. Note that you will have problems if you try to \fBasciiplot\fR
something with an X-scale that isn't monotonic (i.e, something
like \fIsin(TIME)\fR ), because \fBasciiplot\fR uses a simple-minded sort
of linear interpolation.
.TP
\fBdefine function(arg1, arg2, ...) expression\fR
Define the \fIuser-definable function\fR with the name \fIfunction\fR
and arguments \fIarg1, arg2, ...\fR to be \fIexpression\fR, which
may involve the arguments. When the function is later used, the arguments
it is given are substituted for the formal arguments when it is parsed.
If \fIexpression\fR is not present, any definition for \fIfunction\fR
is printed, and if there are no arguments to \fIdefine\fR then all
currently active definitions are printed. Note that you may have different
functions defined with the same name but different arities.
Some useful definitions are:
.IP
define max(x,y) (x > y) * x + (x <= y) * y
.br
define min(x,y) (x < y) * x + (x >= y) * y
.TP
\fBundefine function ...\fR
Definitions for the named user-defined functions are deleted.
.TP
\fBlet name = expr\fR
Creates a new vector called
.B name
with the value specified by
.B expr,
an expression as described above. If \fBexpr\fR is [] (a zero-length vector)
then the vector becomes undefined.
If there are no arguments, \fBlet\fR is the same as \fBdisplay\fR.
.TP
\fBprint [col] [line] expr ... \fR
Prints the vector described by the expression
.B expr.
If the 
.B col
argument is present, print the vectors named side by side. If \fBline\fR
is given, the vectors are printed horizontally.  \fBcol\fR is the default,
unless all the vectors named have a length of one, in which case \fBline\fR
is the default.
The options
\fBwidth, length,\fR and \fBnobreak\fR are effective for this
command (see \fBasciiplot\fR). If the expression is \fBall\fR,
all of the vectors available are printed. Thus \fBprint col all > file\fR
will print everything in the file in \s-2SPICE\s+2\&2 format.
The scale vector (time, frequency) will always be in the first column
unless the variable \fBnoprintscale\fR is true.
.TP
\fBload [filename] ... \fR
Loads the raw data in either binary or ascii format
from the files named. The default filename is \fBrawspice\fR, or the argument
to the \fB-r\fR flag if there was one.
.TP
\fBsource filename\fR
Reads commands from the file
.B filename.
Lines beginning with the character \fB*\fR are considered comments and
ignored.
.TP
\fBhelp [all] [command ...]\fR
Prints help.  If the argument \fBall\fR is given, a short description
of everything you could possibly type is printed.  If \fBcommand\fRs are
given, descriptions of those commands are printed.  Otherwise help for
only a few major commands is printed.
.TP
\fBdisplay [varname ...]\fR
Prints a summary of currently defined vectors, or of the names specified.
The vectors are sorted by name unless the variable \fBnosort\fR is set.
The information given is the name of the vector, the length, the
type of the vector, and whether it is real or complex data. Additionally,
one vector will be labeled \fB[scale]\fR. When a command such as
\fIplot\fR is given without a \fIvs\fR argument, this scale is used
for the X-axis. It is always the first vector in a rawfile, or
the first vector defined in a new plot. If you undefine the scale
(i.e, \fIlet TIME = []\fR), a random remaining
vector will become the scale.
.TP
\fBsetplot [plotname]\fR
Set the \fBcurrent plot\fR to the plot with the given
name, or if no name is given, prompt the user with a menu. 
(Note that the plots are named as they are loaded, with names
like \fBtran1\fR or \fBop2\fR. These names are shown by the
\fBsetplot\fR and \fBdisplay\fR commands and are used by \fBdiff\fR,
below.)
If the
"New plot" item is selected, the current plot will become one with
no vectors defined.
Note that here the word "plot" refers
to a group of vectors that are the result of one \s-2SPICE\s+2 run.
When
more than one file is loaded in, or more than one plot is present
in one file, \fBnutmeg\fR keeps them seperate and only shows you the
vectors in the current plot.
.TP
\fBsettype type vector ...\fR
Change the type of the named vectors to \fBtype\fR.  Type names can
be found in the manual page for \fBsconvert\fR.
.TP
\fBdiff plot1 plot2 [vec ...]\fR
Compare all the vectors in the specified \fIplots\fR, or only the named
vectors if any are given. There are different vectors in the two plots,
or any values in the vectors differ significantly the difference is
reported. The variables \fBabstol, reltol,\fR and \fBvntol\fR are used
to determine what "significantly" means (see the \s-2SPICE\s+2\&3 User's
Manual).
.TP
.B quit
Quit nutmeg.
.TP
.B bug
Send a bug report. (If you have defined BUGADDR, the mail will go there.)
.TP
\fBwrite [file] [exprs]\fR
Writes out the expr's to
.B file.
First vectors are grouped together by plots, and written out as such.
(I.e, if the expression list contained three vectors from one plot
and two from another, then two plots will be written, one with three
vectors and one with two.)  Additionally, if the scale for a vector
isn't present, it is automatically written out as well.
The default format
is ascii, but this can be changed with the \fBset filetype\fR command.
The default filename is \fBrawspice\fR, or the argument to the \fB-r\fR
flag on the command line, if there was one, and the default expression
list is \fBall\fR.
.TP
\fBshell [args ...]\fR
Fork a shell, or execute the arguments as a command to the shell.
.TP
\fBalias [word] [text ...]\fR
Causes \fBword\fR to be aliased to \fBtext\fR.  History substitutions may
be used, as in C-shell aliases.
.TP
\fBunalias [word ...]\fR
Removes any aliases present for the \fBword\fRs.
.TP
\fBhistory [number]\fR
Print out the history, or the last \fBnumber\fR commands typed at the keyboard.
\fINote:\fR in \*S version 3a7 and earlier, all commands (including ones read
from files) were saved.
.TP
\fBset [word] [word = value] ... \fR
Set the value of \fBword\fR to be \fBvalue\fR, if it is present.
You can set any word to be any value, numeric or string.  If no value is
given then the value is the boolean 'true'.   The value of \fIword\fR may
be inserted into a command by writing \fI$word\fR.
If a variable is set to a list of values that are enclosed in parentheses 
(which
\fBmust\fR be seperated from their values by white space), the value
of the variable is the list.
The variables meaningful to \fBnutmeg\fR (of which there are too many) are:
.IP "" 16
\fBabstol\fR
.br
The absolute tolerance used by the \fBdiff\fR command.
.IP
\fBappendwrite\fR
.br
Append to the file when a \fBwrite\fR command is issued, if one
already exists.
.IP
\fBcolor\fIN\fR
.br
These variables determine the colors used, if \fBX\fR is being run on
a color display.
\fIN\fR may be between 0 and 15.  Color 0 is the background, color 1
is the grid and text color, and colors 2 through 15 are used in order for
vectors plotted.  The value of the \fBcolor\fR variables should be names
of colors, which may be found in the file \fB/usr/lib/rgb.txt\fR.
.IP
\fBcombplot\fR
.br
Plot vectors by drawing a vertical line from each point to the X-axis,
as opposed to joining the points.  Note that this option is subsumed
in the \fIplottype\fR option, below.
.IP
\fBcpdebug\fR
.br
Print \fIcshpar\fR debugging information. (Must be complied with the
-DCPDEBUG flag.)
.IP
\fBdebug\fR 
.br
If set then a lot of debugging information is printed. (Must be
compiled with the -DFTEDEBUG flag.)
.IP
\fBdevice\fR
.br
The name (/dev/tty??) of the graphics device. If this variable
isn't set then the user's terminal is used. To do plotting on
another monitor you will probably have to set both the \fBdevice\fR
and \fBterm\fR variables.  (If \fBdevice\fR is set to the name of
a file, \fBnutmeg\fR will dump the graphics control codes into
this file -- this is useful for saving plots.)
.\".IP
.\"\fBdontplot\fR 
.\".br
.\"No graphics control codes are actually sent. (Useful for debugging on
.\"non-graphics terminals.)
.IP
\fBecho\fR 
.br
Print out each command before it is executed.
.IP
\fBfiletype\fR
.br
This can be either
.B ascii
or
.B binary,
and determines what the format of
.I rawfiles
will be. The default is
.B ascii.
.IP
\fBfourgridsize\fR
.br
How many points to use for interpolating into when doing fourier analysis.
.\".IP
.\"\fBgeometry\fIN\fR
.\".br
.\"The size and positioning information for X windows.  \fIN\fR may be
.\"any positive integer, in which case it is the information for the \fIN\fR'th
.\"window on the screen, or may be omitted, in which case it is used whenever
.\"there is no information for the window.  The geometry information is a string
.\"of the form \fR=\fIheight\fBx\fIwidth\fB+\fIxoff\fB+\fIyoff\fR, where the
.\"window will be of size \fIheight\fR by \fIwidth\fR and be positioned at
.\"(\fIxoff, yoff\fR), where (0,0) is the upper left hand corner of the screen.
.\"Either the positioning information or the size information may be omitted,
.\"in which case the window will be opened interactively (as will happen if no
.\"\fBgeometry\fR information is given).  The method of interactive sizing is
.\"the same as for other X utilities.
.\"A typical use for the \fBgeometry\fR variables might be to set \fBmaxwins\fR
.\"to 3 and set \fBgeometry1, geometry2,\fR and \fBgeometry3\fR to position three
.\"plot windows in a row across the top of the screen.
.IP
\fBgridsize\fR
.br
If this variable is set to an integer, this number will be used as the number
of equally spaced points to use for the Y-axis when plotting.  Otherwise
the current scale will be used (which may not have equally spaced points).
If the current scale isn't strictly monotonic, then this option will have
no effect.
.IP
\fBhcopydev\fR
.br
If this is set, when the \fBhardcopy\fR command is run the resulting file
is automatically printed on the printer named \fBhcopydev\fR with the
command \fIlpr -P\fBhcopydev\fI -g \fBfile\fR.
.IP
\fBhcopydevtype\fR 
.br
This variable specifies the type of the printer output to use in the
\fBhardcopy\fR command.  If hcopydevtype is not set, plot (5) format
is assumed.  The standard distribution currently recognizes \fBpostscript\fR
as an alternative output format.  When used in conjunction with
\fBhcopydev\fR, \fBhcopydevtype\fR should specify a format supported by
the printer.
.IP
\fBheight\fR 
.br
The length of the page for \fBasciiplot\fR and \fBprint col\fR.
.IP
\fBhistory\fR 
.br
The number of events to save in the history list.
.\".IP
.\"\fBmaxwins\fR
.\".br
.\"The maximum number of windows X should have on the screen at one time.
.\"If it has \fBmaxwins\fR or more windows, it will begin re-using them
.\"for plots in an oldest-first manner.
.IP
\fBnfreqs\fR
.br
The number of frequencies to compute in the
.B fourier
command. (Defaults to 10.)
.IP
\fBnobreak\fR 
.br
Don't have \fBasciiplot\fR and \fBprint col\fR break between pages.
.IP
\fBnoasciiplotvalue\fR
.br
Don't print the first vector plotted to the left when doing an
\fBasciiplot\fR.
.IP
\fBnoclobber\fR 
.br
Don't overwrite existing files when doing IO redirection.
.IP
\fBnoglob\fR
.br
Don't expand the global characters `*', `?', `[', and `]'. This is the
default.
.IP
\fBnogrid\fR
.br
Don't plot a grid when graphing curves (but do label the axes).
.IP
\fBnomoremode\fR
.br
If \fBnomoremode\fR is not set, whenever a large amount of data is being
printed to the screen (e.g, the \fBprint\fR or \fBasciiplot\fR commands),
the output will be stopped every screenful and will continue when
a carriage return is typed. If \fBnomoremode\fR is set then data will scroll
off the screen without hesitation.
.IP
\fBnonomatch\fR
.br
If \fBnoglob\fR is unset and a global expression cannot be matched, use
the global characters literally instead of complaining.
.IP
\fBnosort\fR 
.br
Don't have \fBdisplay\fR sort the variable names.
.IP
\fBnoprintscale\fR 
.br
Don't print the scale in the leftmost column when a \fBprint col\fR command
is given.
.IP
\fBnumdgt\fR
.br
The number of digits to print when printing tables of data (\fBfourier, print
col\fR).  The default precision is 6 digits.  On the VAX, approximately
16 decimal digits are available using double precision, so \fBnumdgt\fR
should not be more than 16.  If the number is negative, one fewer digit
is printed to ensure constant widths in tables.
.IP
\fBplottype\fR
.br
This should be one of \fInormal\fR, \fIcomb\fR, or \fIpoint:\fBchars\fR.
\fInormal\fR, the  default, causes points to be plotted as parts of connected
lines.  \fIcomb\fR causes a comb plot to be done (see the description of the
\fIcombplot\fR variable above).  \fIpoint\fR causes each point to be plotted
seperately \- the \fBchars\fR are a list of characters that will be used
for each vector plotted.  If they are omitted then a default set is used.
.IP
\fBpolydegree\fR
.br
The degree of the polynomial that the \fBplot\fR command should fit
to the data. If \fIpolydegree\fR is N, then \fBnutmeg\fR will fit a degree N
polynomial to every set of N points and draw 10 intermediate points
in between each endpoint. If the points aren't monotonic, then it will try
rotating the curve and reducing the degree until a fit is achieved.
.IP
\fBpolysteps\fR
.br
The number of points to interpolate between every pair of points available
when doing curve fitting. The default is 10. (This should really be done
automatically.)
.IP
\fBprogram\fR 
.br
The name of the current program (\fIargv[0]\fR).
.IP
\fBprompt\fR 
.br
The prompt, with the character `!' replaced by the current event number.
.IP
\fBrawfile\fR
.br
The default name for rawfiles created.
.IP
\fBreltol\fR
.br
The relative tolerance used by the \fBdiff\fR command.
.IP
\fBrhost\fR
.br
The machine to use for remote \s-2SPICE-3\s+2 runs, instead of the
default one. (See the description of the \fBrspice\fR command,
below.)
.IP
\fBrprogram\fR
.br
The name of the remote program to use in the \fBrspice\fR command.
.\".IP
.\"\fBsavewins\fR
.\".br
.\"If true, then don't get rid of the plot window after the plot is done (X
.\"only).  The window may be removed by clicking any mouse button inside of it.
.IP
\fBslowplot\fR
.br
Stop between each graph plotted and wait for the user to type
return before continuing.
.IP
\fBsourcepath\fR
.br
A list of the directories to search when a \fBsource\fR command is given.
The default is the current directory and the standard spice library
(\fI/usr/local/lib/spice\fR, or whatever \fBLIBPATH\fR is #defined to
in the \*S source.
.IP
\fBspicepath\fR
.br
The program to use for the \fBaspice\fR command. The default is
/cad/bin/spice.
.IP
\fBterm\fR 
.br
The \fImfb\fR name of the current terminal.
.IP
\fBunits\fR 
.br
If this is \fBdegrees\fR, then all the trig functions will use degrees
instead of radians.
.IP
\fBunixcom\fR
.br
If a command isn't defined, try to execute it as a \s-2UNIX\s+2 command.
Setting this option has the effect of giving a \fBrehash\fR command,
below.
This is useful for people who want to use \fBnutmeg\fR as a login shell.
.IP
\fBverbose\fR 
.br
Be verbose. This is midway between \fBecho\fR and \fBdebug\fR / \fBcpdebug\fR.
.IP
\fBvntol\fR
.br
The absolute voltage tolerance used by the \fBdiff\fR command.
.IP
\fBwidth\fR 
.br
The width of the page for \fBasciiplot\fR and \fBprint col\fR.
.IP
\fBxbrushheight\fR
.br
The height of the brush to use if \fBX\fR is being run.
.IP
\fBxbrushwidth\fR
.br
The width of the brush to use if \fBX\fR is being run.
.IP
\fBxfont\fR
.br
The name of the X font to use when plotting data and entering labels.
The plot may not look entirely great if this is a variable-width font.
.PP
.TP
\fBunset [word] ... \fR
Unset the variables \fBword\fR.
.TP
\fBshift [varname] [number]\fR
If \fIvarname\fR is the name of a list variable, it is shifted to the left
by \fInumber\fR elements. (I.e, the \fInumber\fR leftmost elements are
removed.)  The default \fIvarname\fR is \fBargv\fR, and the default
\fInumber\fR is 1.
.TP
\fBrusage [resource ...]\fR
Print resource usage statistics.  If any \fBresource\fR\&s are given,
just print the usage of that resource.  Currently valid \fBresource\fR\&s
are:
.IP "" 16
\fBelapsed\fR
.br
The amount of time elapsed since the last \fBrusage elaped\fR call.
.IP
\fBfaults\fR
.br
Number of page faults and context switches (BSD only).
.IP
\fBspace\fR
.br
Data space used.
.IP
\fBtime\fR
.br
CPU time used so far.
.IP
\fBeverything\fR
.br
All of the above.
.TP
\fBcd [directory]\fR
Change the current working directory to \fBdirectory\fR, or to the user's
home directory if none is given.
.TP
\fBaspice [output-file]\fR
Start a \s-2SPICE-3\s+2 run, and when it is finished load the data. The
raw data is kept in a temporary file. If \fIoutput-file\fR is specified
then the diagnostic output is directed into that file, otherwise it
is thrown away.
.TP
\fBjobs\fR
Report on the asynchronous \s-2SPICE-3\s+2 jobs currently running.
\fBNutmeg\fR checks to see if the jobs are finished every time you
execute a command.
If it is done then the data is loaded and becomes available.
.TP
\fBrspice [input file]\fR
Runs a \s-2SPICE-3\s+2 remotely taking the \fBinput file\fR as a
\s-2SPICE-3\s+2 input deck, or the current circuit if no argument is
given. \fBNutmeg\fR waits for the job to complete, and passes output
from the remote job to the user's standard output. When the job is
finished the data is loaded in as with \fRaspice\fR. If the variable
\fIrhost\fR is set, \fBnutmeg\fR will connect to this host instead of
the default remote \s-2SPICE-3\s+2 server machine. Note that this
command will only work if your system administrator is running a
\s-2SPICE-3\s+2 daemon on the remote host. If the variable \fIrprogram\fR
is set, then \fBrspice\fR will use this as the pathname to the program
to run.
.TP
\fBecho [stuff...]\fR
Echos the arguments.
.TP
\fBfourier fundamental_frequency [value ...]\fR
Does a fourier analysis of each of the given values, using the first 10
multiples of the fundamental frequency (or the first \fInfreqs\fR, if that
variable is set \- see below). The output is like that of 
the \fB.four\fR \*S card. The values may be any valid expression.
The values are interpolated onto a fixed-space grid with the number of
points given by the \fBfourgridsize\fR variable, or 200 if it is not set.
The interpolation will be of degree \fBpolydegree\fR if that variable is
set, or 1.  If \fBpolydegree\fR is 0, then no interpolation will be done.
This is likely to give erroneous results if the time scale is not monotonic,
though.
.TP
\fBversion [version id]\fR
Print out the version of \fBnutmeg\fR that is running.
If there are arguments, it checks to make sure that the arguments match
the current version of \s-2SPICE\s+2. (This is mainly used as a \fBCommand:\fR
line in rawfiles.)
.TP
\fBrehash\fR
Recalculate the internal hash tables used when looking up UNIX commands,
and make all UNIX commands in the user's PATH available for command
completion.
This is useless unless you have \fBset unixcom\fR first (see above).
.PP
The following control structures are available:
.IP
.nf
\fBwhile\fR \fIcondition\fR
	statement
	...
\fBend\fR
.fi
.PP
While \fIcondition\fR, an arbitrary algebraic expression, is true,
execute the statements.
.IP
.nf
\fBrepeat\fR \fI[number]\fR
	statement
	...
\fBend\fR
.fi
.PP
Execute the statements \fInumber\fR times, or forever if no argument is
given.
.IP
.nf
\fBdowhile\fR \fIcondition\fR
	statement
	...
\fBend\fR
.fi
.PP
The same as \fBwhile\fR, except that the \fIcondition\fR is tested after
the statements are executed.
.IP
.nf
\fBforeach\fR \fIvar\fR \fIvalue ...\fR
	statement
	...
\fBend\fR
.fi
.PP
The statements are executed once for each of the \fIvalue\fRs, each time
with the variable \fIvar\fR set to the current one.  (\fIvar\fR can be accessed
by the $\fIvar\fR notation \- see below).
.IP
.nf
\fBif\fR \fIcondition\fR
	statement
	...
\fBelse\fR
	statement
	...
\fBend\fR
.fi
.PP
If the \fIcondition\fR is non-zero then the first set of statements are
executed, otherwise the second set.  The \fBelse\fR and the second set
of statements may be omitted.
.IP
\fBlabel\fR \fIword\fR
.PP
If a statement of the form \fBgoto\fI word\fR is encountered, control is
transfered to this point, otherwise this is a no-op.
.IP
\fBgoto\fR \fIword\fR
.PP
If a statement of the form \fBlabel\fI word\fR is present in the block
or an enclosing block, control is transfered there.  Note that if the
label is at the top level, it \fImust\fR be before the \fBgoto\fR statement
(i.e, a forward \fBgoto\fR may occur only within a block).
.IP
\fBcontinue\fR
.PP
If there is a \fBwhile, dowhile,\fR or \fBforeach\fR block enclosing this
statement, control passes to the test, or in the case of \fBforeach\fR,
the next value is taken.
Otherwise an
error results.
.IP
\fBbreak\fR
.PP
If there is a \fBwhile, dowhile,\fR or \fBforeach\fR block enclosing this
statement, control passes out of the block. Otherwise an
error results.
.PP
Of course, control structures may be nested.  When a block is entered
and the input is the terminal, the prompt becomes a number of >'s
equalling the number of blocks the user has entered. The current control
structures may be examined with the debugging command
.B cdump.
.PP
If a word is typed as a command, and there is no built-in command
with that name, the directories in the \fIsourcepath\fR list are searched
in order for the file.  If it is found, it is read in as a command file (as
if it were \fBsource\fRd).  Before it is read, however, the variables
\fIargc\fR and \fIargv\fR are set to the number of words following the
filename on the command line, and a list of those words respectively.
After the file is finished, these variables are \fBunset\fR.  Note that
if a command file calls another, it must save its \fIargv\fR and \fIargc\fR
since they will get altered.  Also, command files may not be re-entrant
since there are no local variables.  (Of course, the procedures may
explicitly manipulate a stack...)
This way one can write scripts analogous to shell scripts for \fBnutmeg\fR and
\*S.  Note that for the script to work with \*S, it \fBmust\fR begin
with a blank line (or whatever you like, since it will be thrown away)
and then a line with \fB.control\fR on it.  This is an unfortunate result
of the \fBsource\fR command being used for both circuit input and command
file execution.  Note also that this allows the user to merely type the
name of a circuit file as a command, and it will be automatically run.
.PP
There are various command scripts installed in
\fI/usr/local/lib/spice/scripts\fR (or whatever the path is on your machine),
and the default \fIsourcepath\fR includes this directory, so you can use
these command files (almost) like builtin commands.  
.PP
\fBNutmeg\fR will use either \fBX\fR or \fBMFB\fR, depending on whether
it finds the variable \fBDISPLAY\fR in the environment.  If you are
using \fBX\fR on a workstation, it should already be present, but if you
want to display graphics on a different machine than the one you
are running \fBnutmeg\fR on, \fBDISPLAY\fR should be of the form 
\fImachine\fR:0.
.PP
If \fBX\fR is being used, the cursor may be positioned at any
point on the screen when the window is up and characters typed at the
keyboard will be added to the window at that point.  The window may
then be sent to a printer using the \fBxpr(1)\fR program.
.PP
There are a number of pre-defined constants in \fBnutmeg\fR. They are:
.na
.nf
	pi		pi
	e		The base of natural logarithms
	c		The speed of light
	i		The square root of -1
	kelvin		Absolute 0 in Centigrade
	echarge		The charge on an electron
	boltz		Boltzman's constant
	planck		Planck's constant (h)

.fi
.ad
.PP
These are all in MKS units. If you have another variable with
a name that conflicts with one of these then it takes precedence.
.PP
Nutmeg occasionally checks to see if it
is getting close to running out of space, and warns the user if this
is the case. (This is more likely to be useful with the \s-2SPICE\s+2
front end.)
.PP
C-shell type quoting with "" and '', and backquote substitution may
be used. Within single quotes, no further substitution (like
history substitution) is done, and within double quotes, the words
are kept together but further substitution is done. Any text between
backquotes is replaced by the result of executing the text as a command
to the shell.
.PP
Tenex-style ('set filec' in the 4.3 C-shell)
command, filename, and keyword completion is possible: If EOF
(control-D) is typed after the first character on the line, a list
of the commands or possible arguments is printed. (If it is alone
on the line it will exit \fBnutmeg\fR.) If escape is typed, then
\fBnutmeg\fR will try to complete what the user has already typed.
To get a list of all commands, the user should type <space> ^D.
.PP
The values of variables may be used in commands by writing \fB$varname\fR
where the value of the variable is to appear.  The special variables
\fI$$\fR and \fI$<\fR refer to the process ID of the program and a
line of input which is read from the terminal when the variable
is evaluated, respectively.  If a variable has a name of the form
\fB$&word\fR, then \fBword\fR is considered a vector (see above),
and its value is taken to be the value of the variable.
If \fI$foo\fR is a valid variable, and is of type \fBlist\fR, then the
expression \fI$foo[low-high]\fR represents a range of elements.  Either
the upper index or the lower may be left out, and the reverse of a list may
be obtained with \fI$foo[len-0]\fR.  Also, the notation \fI$?foo\fR evaluates
to 1 if the variable \fIfoo\fR is defined, 0 otherwise, and \fI$#foo\fR
evaluates to the number of elements in \fIfoo\fR if it is a list, 1 if it
is a number or string, and 0 if it is a boolean variable.
.PP
History substitutions, similar to C-shell history substitutions, are
also available \- see the C-shell manual page for all of the details.
.PP
The characters ~, {, and } have the same effects as they do in the
C-Shell, i.e., home directory and alternative expansion. It is
possible to use the wildcard characters *, ?, [, and ] also,
but only if you \fBunset noglob\fR first. This makes them rather
useless for typing algebraic expressions, so you should \fBset noglob\fR
again after you are done with wildcard expansion. Note that the
pattern \fB[^abc]\fR will match all characters \fIexcept\fB a, b, 
\fRand\fB c.\fR
.PP
IO redirection is available \- the symbols \fB>, >>, >&, >>&, \fRand\fB <\fR
have the same effects as in the C-shell.
.PP
You may type multiple commands on one line, seperated by semicolons.
.PP
If you want to use a different \fBmfbcap\fR file than the default (usually
\fB~cad/lib/mfbcap\fR), you have to set the environment variable \fBMFBCAP\fR
before you start \fBnutmeg\fR.  The \fB-m\fR option and the \fBmfbcap\fR
variable no longer work.
.SH "VMS NOTES"
\fBNutmeg\fR can be run under VAX/VMS. Some features like command, etc
completion, expansion of *, ?, and [], backquote substitution, the
shell command, and so forth do not work. (In fact command completion
only works on 4.2 or 4.3 BSD.) 
.PP
\fBNutmeg\fR will look for start-up
commands in the file \fIspice.rc\fR in the current directory.
.PP
The standard suffix for rawspice files in VMS is ".raw".
.PP
You will have to respond to the \fI-more-\fR prompt during plot with a
carriage return instead of any key as you can do on UNIX.
.SH "SEE ALSO"
sconvert(1), spice(1), mfb(3), writedata(3)
.SH AUTHOR
Wayne Christopher (faustus@cad.berkeley.edu)
.SH BUGS
.PP
The label entry facilities are very primitive \- after all, \fBnutmeg\fR isn't
a graphics editor (yet).  You must be careful to type very slowly when
entering labels -- \fBnutmeg\fR checks the \fBX\fR event queue once
every second, and can get very confused if characters arrive faster than
that.
.PP
If you redefine colors after creating a plot window with X, and then
cause the window to be redrawn, it will not to the right thing.
.PP
When defining aliases like
.IP
\fIalias pdb plot db( '!:1' - '!:2' )\fR
.PP
you must be careful to quote the argument list substitutions in this
manner. If you quote the whole argument it might not work properly.
.PP
In a user-defined function, the arguments cannot be part of a name that
uses the \fIplot.vec\fR syntax.  I.e,
.IP
\fIdefine poke(duck) cos(tran1.duck)
.PP
won't do the right thing.
.PP
If you type \fBplot all all\fR, or otherwise use a wildcard reference for
one plot twice in a command, bad things will happen.
.PP
The \fBasciiplot\fR command doesn't deal with log scales or the \fBdelta\fR
keywords.
.PP
There are probably some features that \fBnutmeg\fR doesn't have yet.
.SH CAVEATS
Often the names of terminals recognised by \fBMFB\fR are different
from those in /etc/termcap. Thus you may have to reset your terminal
type with the command
.IP
\fBset term = termname\fR
.PP
where \fBtermname\fR is the name in the \fBmfbcap\fR file.
.PP
The \fBhardcopy\fR command is useless on VMS and other systems without
the \fBplot\fR command, unless the user has a program that understands
\fIplot(5)\fR format.