gnuplot

Function

(gnuplot file {setting value}* {plot {setting value}*}+)

Creates a Gnuplot file containing (optional) global file settings followed by one or more plots with (optional) plot-specific settings. Each plot is a list or seq in one of the following formats:

( (c1 c2 ... cn) ...)

A list of lists where each sublist defines the "columns" of a Gnuplot point record.

(x1 y1 x2 y2 ... xn yn)

A flat list of x y point data.

(v1 v2 ... vn)

A flat list of values to graph in left-to-right order along the x axis.

(object1 object2 ... objectn )

A flat list of CLOS objects whose slots are graphed according to the :points setting.

Of these formats, only the first (point record) format is directly supported by Gnuplot. The other (flat list) formats require an interpretation of their data. The special :points setting described below can be used to specify the format of plots globally or individually. The function will attempt to determine the format of any flat list plot without a :points specification.

Settings

In general, each setting is the keyword name of a Gnuplot setting followed by its value. Settings that appear before the first plot become (global) gnuplot set command directives, e.g :title "Hiho" becomes set title "HiHo" in the gnuplot file. Settings that appear after a plot are unique to that plot.

Setting values are interpreted in the following way:

• Numbers and strings are passed directly to gnuplot without any interpretation. This means that a string can pass a multi-word gnuplot clause including spaces and commas.
• Keywords are treated specially by some settings (see the :style setting) else they are converted to a lowercase string and printed to the file.
• Symbols are converted to lowercase strings and printed to the file.
• Lists are clause groupings or range specifications.

gnuplot supports following non-Gnu settings:

:view bool

If true then the gnuplot program is automatically called with file after it has been written. The default value is true.

:points { int | :y | :xy | slot | (slot1 ...)}

Identifies the point format in flat lists of data. An integer value groups that many values into each point record, e.g. 2 means that each pair of values becomes a point record in the gnuplot file. The values :y and :xy can be used in place of 1 and 2, respectively. Otherwise the value should be the slot name (symbol) or list of slot names to access in a flat list of CLOS objects.

:comment string

Optional comment string to appear as the first line of file.

gnuplot alters the syntax of the following Gnu settings:

:style {plotstyle}

A keyword plotstyle is expanded to the proper command form 'set style data {plotstyle}'. Valid plotting styles are

:lines :points :linespoints :impulses :dots :steps :fsteps :histeps :errorbars :xerrorbars :yerrorbars :xyerrorbars :errorlines :xerrorlines :yerrorlines :boxes :filledboxes :filledcurves :boxederrorbars :boxxyerrorbars :financebars :candlesticks :vector

See Gnuplot plotting styles for more information.

:[txy]range (low high)

The value is a list of two values. These global axis settings can be applied to individual plots as well.

Examples

;; Plotting data sets
(gnuplot "test.plt" '( 0 0 50 .9 100 0) )

(gnuplot "test.plt" :title "My envelopes"
	 '(0 0 25 .9 75 .9 100 0) :title "ramp"	
	 '(0 1 5 .5 10 .1 100 0) :title "expt" 
	 '(0 0 50 1 100 0) :title "updown")

(gnuplot "test.plt" :title "Random numbers" 
	 :points :y
         :style :impulses
	 (loop repeat 20 collect (random 1.0)))

(gnuplot "test.plt" :title "Hi Ho!" :nokey #t
	 '(0 0 25 .9 80 .5 100 0) 
	 :with :linespoints
	 (loop for i to 100 by 10 
               collect i collect (random 1.0))
	 :with :points)

(gnuplot "test.plt" :title "Random Midis"
	 :points '(time keynum duration)
	 :style :xerrorbars
	 :yrange '(60 100)
	 (loop repeat 20 
	    for beg = 0 then (+ beg (random 1.0))
	    for dur = (pick .1 .2 .3)
	    for key = (between 70 80)
	    collect (new midi :time beg :keynum key 
			 :duration dur)))

Variables

*gnuplot*

The shell command (string) to start gnuplot. Defaults to "gnuplot".

*gnuplot-default-settings*

A list of default settings passed to Gnuplot. Defaults to (:view #t :style :linespoints).

See also

• gnuplot-file [Class]