C Copyright (C) 1986 - 1993, 1998, 1999, 2000, 2001, 2004 Thomas Williams, Colin Kelley et al.

C

1 Gnuplot

?gnuplot

^<h2 align="center"> An Interactive Plotting Program </h2>

^<p align="center"> Thomas Williams & Colin Kelley</p>

^<p align="center"> Version 5 organized by Ethan A Merritt and others</p>

^<p align="center">Major contributors (alphabetic order):<br>

^<br>

^ Hans-Bernhard Broeker, John Campbell,<br>

^ Robert Cunningham, David Denholm,<br>

^ Gershon Elber, Roger Fearick,<br>

^ Carsten Grammes, Lucas Hart, Lars Hecking,<br>

^ Péter Juhász, Thomas Koenig, David Kotz,<br>

^ Ed Kubaitis, Russell Lang, Timothée Lecomte,<br>

^ Alexander Lehmann, Alexander Mai, Bastian Märkisch,<br>

^ Tatsuro Matsuoka, Ethan A Merritt, Petr Mikulík,<br>

^ Carsten Steger, Shigeharu Takeno,<br>

^ Tom Tkacik, Jos Van der Woude,<br>

^ James R. Van Zandt, Alex Woo, Johannes Zellner<br>

^</p>

^<p align="center"> Copyright (C) 1986 - 1993, 1998 - 2004 Thomas Williams, Colin Kelley<br>

^ Copyright (C) 2004 - 2022 various authors</p>

^<p align="center"> Mailing list for comments: <tt>[email protected]</tt><br>

^ Gnuplot <a href="http://gnuplot.info"> home page </a><br>

^ Issue trackers: &nbsp;

^<a href="https://sourceforge.net/p/gnuplot/bugs"> bugs </a> &nbsp;&nbsp;

^<a href="https://sourceforge.net/p/gnuplot/feature-requests"> feature requests </a>

^<p align="center"> This manual was originally prepared by Dick Crawford</p>

^<!-- end of titlepage -->

2 Copyright

?copyright

?license

Copyright (C) 1986 - 1993, 1998, 2004, 2007 Thomas Williams, Colin Kelley

Permission to use, copy, and distribute this software and its

documentation for any purpose with or without fee is hereby granted,

provided that the above copyright notice appear in all copies and

that both that copyright notice and this permission notice appear

in supporting documentation.

Permission to modify the software is granted, but not the right to

distribute the complete modified source code. Modifications are to

be distributed as patches to the released version. Permission to

distribute binaries produced by compiling modified sources is granted,

provided you

1. distribute the corresponding source modifications from the

released version in the form of a patch file along with the binaries,

2. add special version identification to distinguish your version

in addition to the base release version number,

3. provide your name and address as the primary contact for the

support of your modified version, and

4. retain our contact information in regard to use of the base software.

Permission to distribute the released version of the source code along

with corresponding source modifications in the form of a patch file is

granted with same provisions 2 through 4 for binary distributions.

This software is provided "as is" without express or implied warranty

to the extent permitted by applicable law.

AUTHORS

Original Software:

Thomas Williams, Colin Kelley.

Gnuplot 2.0 additions:

Russell Lang, Dave Kotz, John Campbell.

Gnuplot 3.0 additions:

Gershon Elber and many others.

Gnuplot 4.0 and 5.0 additions:

See list of contributors at head of this document.

2 Introduction

?introduction

?

`Gnuplot` is a portable command-line driven graphing utility for Linux, OS/2,

MS Windows, OSX, VMS, and many other platforms. The source code is copyrighted

but freely distributed (i.e., you don't have to pay for it). It was originally

created to allow scientists and students to visualize mathematical functions

and data interactively, but has grown to support many non-interactive uses

such as web scripting. It is also used as a plotting engine by third-party

applications like Octave. Gnuplot has been supported and under active

development since 1986.

Gnuplot supports many types of plots in either 2D and 3D. It can draw using

lines, points, boxes, contours, vector fields, surfaces, and various

associated text. It also supports various specialized plot types.

Gnuplot supports many different types of output: interactive screen terminals

(with mouse and hotkey input), direct output to pen plotters or modern

printers, and output to many file formats (eps, emf, fig, jpeg, LaTeX, pdf, png,

postscript, ...). Gnuplot is easily extensible to include new output modes.

Recent additions include interactive terminals based on wxWidgets (usable

on multiple platforms), and Qt. Mouseable plots embedded in web pages

can be generated using the svg or HTML5 canvas terminal drivers.

The command language of `gnuplot` is case sensitive, i.e. commands and

function names written in lowercase are not the same as those written in

capitals. All command names may be abbreviated as long as the abbreviation is

not ambiguous. Any number of commands may appear on a line, separated by

semicolons (;). Strings may be set off by either single or double quotes,

although there are some subtle differences. See `syntax` and `quotes` for

more details. Example:

set title "My First Plot"; plot 'data'; print "all done!"

Commands may extend over several input lines by ending each line but the last

with a backslash (\). The backslash must be the _last_ character on each

line. The effect is as if the backslash and newline were not there. That

is, no white space is implied, nor is a comment terminated. Therefore,

commenting out a continued line comments out the entire command

(see `comments`). But note that if an error occurs somewhere on a multi-line

command, the parser may not be able to locate precisely where the error is

and in that case will not necessarily point to the correct line.

In this document, curly braces ({}) denote optional arguments and a vertical

bar (|) separates mutually exclusive choices. `Gnuplot` keywords or `help`

topics are indicated by backquotes or `boldface` (where available). Angle

brackets (<>) are used to mark replaceable tokens. In many cases, a default

value of the token will be taken for optional arguments if the token is

omitted, but these cases are not always denoted with braces around the angle

brackets.

For built-in help on any topic, type `help` followed by the name of the topic

or `help ?` to get a menu of available topics.

A large set of demo plots is available on the web page

^ <a href="http://www.gnuplot.info/demo/">

http://www.gnuplot.info/demo/

^ </a>

When run from command line, gnuplot is invoked using the syntax

gnuplot {OPTIONS} file1 file2 ...

where file1, file2, etc. are input file as in the `load` command.

On X11-based systems, you can use

gnuplot {X11OPTIONS} {OPTIONS} file1 file2 ...

see your X11 documentation and `x11` in this document.

Options interpreted by gnuplot may come anywhere on the line. Files are

executed in the order specified, as are commands supplied by the -e option,

for example

gnuplot file1.in -e "reset" file2.in

The special filename "-" is used to force reading from stdin. `Gnuplot` exits

after the last file is processed. If no load files are named, `Gnuplot` takes

interactive input from stdin. See help `batch/interactive` for more details.

The options specific to gnuplot can be listed by typing

gnuplot --help

See `command-line-options` for more details.

In sessions with an interactive plot window you can hit 'h' anywhere on the

plot for help about `hotkeys` and `mousing` features.

Section `seeking-assistance` will help you to find further information, help

and FAQ.

2 Seeking-assistance

?help-desk

?faq

?FAQ

?seeking-assistance

The canonical gnuplot home page can be found at

^ <a href="http://www.gnuplot.info">

http://www.gnuplot.info

^ </a>

Before seeking help, please check file FAQ.pdf or the above website for a

^ <a href="http://www.gnuplot.info/faq/">

FAQ (Frequently Asked Questions) list.

^ </a>

Another resource for help with specific plotting problems (not bugs) is

https://stackoverflow.com/questions/tagged/gnuplot

Bug reports and feature requests should be uploaded to the trackers at

https://sourceforge.net/p/gnuplot/_list/tickets

Please check previous reports to see if the bug you want to report has

already been fixed in a newer version.

When reporting a bug or posting a question, please include full details

of the gnuplot version, the terminal type, and the operating system.

A short self-contained script demonstrating the problem is very helpful.

Instructions for subscribing to gnuplot mailing lists may be

found via the gnuplot development website

^ <a href="http://sourceforge.net/projects/gnuplot">

http://sourceforge.net/projects/gnuplot

^ </a>

Please note that before you write to any of the gnuplot mailing lists you

must first subscribe to the list. This helps reduce the amount of spam.

The address for mailing to list members is:

[email protected]

A mailing list for those interested in the development version of gnuplot is:

[email protected]

2 New features in this version

?new version_5.5

?new

?development version

?version

Version 5.5 is the current development version, built from a snapshot of the

source files in the master branch of the git repository. New features

introduced here will generally not appear in a supported release until

version 5.6. Details may change before that.

For more information about optional features built into the particular copy

of gnuplot you are running, type `show version long`.

3 Special and complex-valued functions

?new math

This version of gnuplot provides a larger set of complex-valued functions and

updated versions of some functions that were present in earlier versions.

#start

#b New: Riemann zeta function with complex domain and range. See `zeta`.

#b Updated lower incomplete gamma function with improved domain and precision.

## Complex arguments accepted.

## See `igamma`.

#b New upper incomplete gamma function (real arguments only).

## See `uigamma`.

#b Updated incomplete beta function with improved domain and precision.

## See `ibeta`.

#b New function for the inverse incomplete gamma function.

## See `invigamma`.

#b New function for the inverse incomplete beta function.

## See `invibeta`.

#b New complex function LambertW(z,k) returns the kth branch of multivalued

## function W_k(z).

^<br>

## Note that the older function lambertw(x) = real(LambertW( real(z), 0 )).

## See `LambertW`.

#b New complex function lnGamma(z).

## Note that existing function lgamma(x) = real(lnGamma(real(z)).

## See `lnGamma`.

#b Complex function conj(z) returns the complex conjugate of z.

#b Synchrotron function F(x), see `SynchrotronF`.

#b acosh(z) domain extended to cover negative real axis.

#b asin(z) asinh(z) improved precision for complex arguments.

#b Predefined variable I = sqrt(-1) = {0,1} for convenience.

^<br>

## This is useful because gnuplot does not accept {a,b} as a valid complex

## constant but does accept (a + b*I) as a valid complex expression.

#end

Additional special functions are supported if a suitable external

library is found at build time. See `special_functions`.

#start

#b Complex Bessel functions Iν(z), Jν(z), Kν(z), Yν(z) of order ν (real)

## with complex argument z. See `BesselK`.

#b Complex Hankel functions H1ν(z), H2ν(z) of order ν with complex z.

## See `BesselH1`.

#b Complex Airy functions Ai(z), Bi(z).

#b Complex exponential integral of order n. See `expint`.

#b Fresnel integrals C(x) and S(x). See `FresnelC`.

#b Function `VP_fwhm(sigma,gamma)` returns the full width at half maximum

## of the Voigt profile. See `VP`, `VP_fwhm`.

#end

3 New plot style

?new style

#start

#b The plot style `with surface` works in 2D polar coordinates to produce

## a solid-fill gridded representation of the plane, colored by weighted

## contributions from an arbitrary set of input points. This is analagous to

## the use of `dgrid3d` and style `with pm3d` to produce a 3D gridded surface.

## See `set polar grid` and `polar heatmap`.

#end

3 Hulls, masks, and smoothing

?new hulls

#start

#b A cluster of 2D points can be replaced by its bounding polygon using the

## new filter `convexhull`. A path-smoothed bounding curve is produced by

## `smooth convexhull`. See `convexhull`.

#b A convex hull or other polygon can be used as a mask to display only

## selected portions of a pm3d surface or an image plot.

## See new plot style `with mask` (defines a mask) and keyword `mask`

## (applies the mask to a subsequent plot component).

#b curve smoothing using along-path cubic splines suitable for closed curves

## or for 2D curves that are not monotonic on x. See `smooth path`.

## This allows smoothing of hulls and masks.

#b cubic spline smoothing of 3D lines. See `splot smooth csplines`

#b Smoothing options apply to plotting `with filledcurves` {above|below|between}.

#b New keyword `period` for smoothing periodic data. See `smooth kdensity`.

#end

3 New data formats

?new data_formats

#start

#b The `sparse matrix=(cols,rows)` option to `plot` and `splot` generates

## a uniform pixel grid into which individual pixel values may be loaded in

## any order. This is useful for plotting heat maps from incomplete data.

## See `sparse`.

#b During input of non-uniform matrix data, column(0) now returns the linear

## ordering of matrix elements. I.e. for element A[i,j] in an MxN matrix A,

## column(0)/M gives the row index i, and column(0)%M gives the column index j.

#end

3 New built-in functions and array operations

?new built-in functions

#start

#b `palette(z)` returns the current RGB palette color mapping z into cbrange.

#b `rgbcolor("name")` returns the 32bit ARGB value for a named color.

#b `index( Array, element )` returns the first index `i` for which

## Array[i] is equal to element. See `arrays`.

#b User-defined functions allow an array as a parameter.

^<br>

## Example: dot(A,B) = sum [i=1:|A|] A[i]*B[i]

#b Array slices are generated by appending a range to the array name.

## Array[n] is single element. Array[n:n+5] is a six element slice of

## the original array. See `arrays`, `slice`.

#b `split("string", "separator")` unpacks the fields in a string into

## an array of strings. See `split`.

#b `join(array, "separator")` is the complement to `split`. It concatenates

## the elements of a string array into a single string with field separators.

## See `join`.

#b `stats <non-existent file>` yields a testable value. See `stats test`.

#b `stats $vgrid` finds min/max/mean/stddev of voxels in grid

#end

3 Function blocks and scoped variables

?new function blocks

This version of gnuplot introduces a mechanism for invoking a block of

standard gnuplot commands as a callable function. A function block can

accept from 0 to 9 parameters and returns a value. Function blocks can be

used to calculate and assign a new value to a variable, to combine with other

functions and operators, or to perform a repetitive task preparing data.

There are three components to this mechanism.

See `local`, `scope`, `function blocks`, `return`.

#start

#b The `local` qualifier allows optional declaration of a variable or array

## whose scope is limited to the duration of execution of the program unit in

## which it is found. These units currently include execution of a

## `load` or `call` statement, function block evaluation, and the code block

## in curly brackets following an `if`, `else`, `do for`, or `while` statement.

## If the name of a local variable duplicates the name of a global variable,

## the global variable is shadowed until exit from the local scope.

#b The `function` command declares a named function block (effectively an

## array of strings) containing gnuplot commands. When the function block

## is invoked, commands are executely successively until the end of the block

## or until a `return` command is encountered.

#b The `return <expression>` command terminates execution of a function block.

## The result of evaluating <expression> is returned as the value of the

## function. Anywhere outside a function block `return` acts like `exit`.

#end

Please see `function_block.dem` for an example of using this mechanism

to define and plot a non-trivial function that is too complicated for a

simple one-line definition `f(x) = ...`.

3 Named palettes

?new colormaps

#start

#b The current palette can be saved to a named colormap for future use.

## See `set colormap`.

#b pm3d and image plots can specify a previously saved palette by name.

## This permits the use of multiple palettes in a single plot command.

## See `colorspec palette`.

#b Named palette colormaps can be manipulated as arrays of 32-bit ARGB

## color values. This permits addition of alpha-channel values or other

## modifications not easily specified in a `set palette` command.

#b There is a new predefined color scheme `set palette viridis`.

#b Palettes read from a file or datablock (`set palette file`) may be specified

## either using fractional color components or 24-bit packed RGB values.

#end

3 Program control flow

?control flow

#start

#b Support XDG base directory for gnuplotrc configuration preferences.

## The program reads initial commands from $HOME/.config/gnuplot/gnuplotrc

## if this file is found. See `environment`.

#b Exception handling for the "fit" command. Control always returns to the

## next line of input, even in the case of fit errors. On return, FIT_ERROR is

## non-zero if an error occurred. This allows scripted recovery from a bad fit.

## See `fit error_recovery`.

#b The `load` and `call` commands can input commands from a datablock as an

## alternative to reading them from a file.

#b New syntax `if ... else if ... else ...`

#b `unset warnings` suppresses output of warning messages to the console.

#end

3 New terminals and terminal options

?new terminals

#start

#b New terminal `block` for text-mode pseudo-graphics uses Unicode

## block or Braille characters to offer improved resolution compared

## to the `dumb` or `caca` terminals.

#b New terminal `webp` generates a single frame or an animation sequence

## using webp encoding. Frames are generated using pngcairo, then

## encoded through the WebPAnimEncoder API exported by libwebp and libwebpmux.

#end

3 Watchpoints

?new watchpoints

Watchpoints are target values associated with individual plots in a graph.

As that plot is drawn, each component line segment is monitored to see if

its endpoints bracket the target value of a watchpoint coordinate (x, y, or z)

or function f(x,y). If a match is found, the [x,y] coordinates of the

match point are saved for later use. See `watchpoints`.

Possible uses include

#start

#b Find the intersection points of two curves

#b Find zeros of a function

#b Find and notate where a dependent variable (y or z) or function f(x,y)

## crosses a threshold value

#b Use the mouse to track values along multiple plots simultaneously

#end

3 Week-date time support

?new week-date time

The Covid-19 pandemic of 2020/2021 generated increased interest in plotting

epidemiological data, which is often tabulated using a "week date" reporting

convention. This revealed deficiencies with gnuplot support for this

convention, including errors in time formats %W and %U. These have now been

remedied and support for week-date time extended.

#start

#b Time specifier format %W has been brought into accord with the

## ISO 8601 week date standard.

#b Time specifier format %U has been brought into accord with the

## CDC/MMWR week date standard.

#b New function `tm_week(time, std)` returns ISO or CDC standard week of year.

#b New function `weekdate_iso(year, week, day)` converts ISO standard week date

## to calendar time.

#b New function `weekdate_cdc(year, week, day)` converts CDC standard week date

## to calendar time.

#end

3 Other new features

?new features

#start

#b `Time units for setting major and minor tics.`

## Both major and minor tics along a time axis now accept tic intervals given

## in units of minutes/hours/days/weeks/months/years.

## See `set xtics`, `set mxtics time`.

#b The character sequence $# in a `using` specifier evaluates to the total

## number of columns available in the current line of data. For example

## "plot FOO using 0:(column($# - 1))" plots the last-but-one field of each row.

#b keyword `binvalue=avg` plots average, rather than sum, of binned data.

#b `set colorbox bottom` places the color box underneath the plot.

#b `set colorbox cbtics <linestyle>` affects cbtics but not other tics.

#b Improved rendering of intersecting pm3d surfaces - overlapping surface tiles

## are split into two pieces along the line of intersection so that tiles

## from one surface do not incorrectly protrude though the other surface.

#b New options to force total key width and number of columns. See `key layout`.

#b `set pm3d border retrace` draws a border around each pm3d quadrangle in the

## same color as the filled area. In principle this should have no visible

## effect, but it prevents some display modes like glitchy pdf or postscript

## viewers from introducing antialiasing artifacts.

#b `set isotropic` adjusts the axis scaling in both 2D and 3D plots such that

## the x, y, and z axes all have the same scale.

#b Change: Text rotation angle is not limited to integral degrees.

#b Special (non-numerical) linetypes `lt nodraw`, `lt black`, `lt bgnd`

## See `special_linetypes`.

#b Data-driven color assignments in histogram plots. See `histograms colors`.

#b The position of the key box can be manually tweaked by specifying an

## offset to be added to whatever position the program would otherwise use.

## See `set key offset`.

#end

3 Features introduced in version 5.4

4 Support for 64-bit integer arithmetic

?version_5.4

New features in 5.4

#start

#b All evaluation of expressions and functions uses 64-integer arithmetic if

## supported by the platform.

#b Integer overflow is detected and handled according to user preference.

## See `overflow`.

#end

4 Voxel grids

Gnuplot now supports operations based on 3D grids of voxel data.

#start

#b `set vgrid $gridname size N` creates an NxNxN grid of voxels.

#b `set vxrange [vxmin:vxmax]` together with `set vyrange` and `set vzrange`

## define which region of space the grid occupies. This may or may not be

## identical to the xyz range of the plot.

#b `voxel(x,y,z)` can be used in expressions to read or write an individual voxel.

#b `vfill DATA_SOURCE using x:y:z:radius:(<expression>)` acts analogously to

## a plot command except that instead of plotting it increments voxels near each

## point in the input data.

#b `vgfill` is a variant of `vfill` that uses grid coordinates rather than

## user coordinates.

#b `vclear $gridname` resets an existing voxel grid to contain all zero values.

#b The current contents of one or more voxel grids can be referenced by

## `splot` commands to assign colors or other properties of plot elements

## by using the `voxel` function in using specifiers.

## See demo `voxel.dem`.

#b `show vgrid` reports basic statistics about all currently defined voxel grids.

#b Voxel grids can also be plotted by name in `splot` commands with plot styles

## `dots`, `points`, or `isosurface`.

## See demo `vplot.dem`.

#end

4 New plot styles and style options

#start

#b 3D plot style `with polygons` reads polygon faces from a data file.

## This can be used to create a surface or to construct a solid object.

## See `with polygons`.

#b `splot $voxelgrid with {dots|points}` marks all voxels whose value is above

## a requested threshold level.

#b `splot $voxelgrid with isosurface` creates a tessellated 3D surface enclosing

## voxels above a requested threshold level. See `isosurface`.

#b Voxel grid values can be referenced in the `using` specifiers for 3D plots.

#b `set spiderplot` selects a new plotting mode allowing creation of spider plots

## (also known as radar charts). These are essentially parallel axis plots where

## the axes are arranged radially rather than vertically.

## See `spiderplot`, `set style spiderplot`, `set paxis`.

#b Plot style `with circles` can be used in 3D plots.

#b Plot style `with boxes` can be used in 3D plots.

#b 2D plot style `with arrows` is identical to `with vectors` except that each

## arrow is specified using x:y:length:angle rather than x:y:xdelta:ydelta

#b splot FOO with pm3d fillcolor <colorspec>

#b pm3d surfaces can have individual fillstyle and separate top/bottom fillcolor

#b pm3d option `noclipcb` causes quadrangles with palette color outside cbrange

## to be skipped rather than being drawn with color clipped to cbmin or cbmax.

#b Customized contour line types. See `set cntrparam`.

#b The vertical lines connecting the base plane to the corners of a 3D surface

## can be toggled on/off. See `set cornerpoles`.

#end

4 New data pre-processing filters

#start

#b `zsort` sorts 2D points on values in a third column. See `zsort`.

## This is useful to bring a small number of salient points in a very large data

## set to the front so that they are not occluded.

#end

4 New commands and command options

#start

#b Voxel grid commands. See `set vgrid`, `set vxrange`, `vclear`, `vfill`,

## `vgfill`, and `voxel`.

#b New options for showing the xy xz and yz planes in 3D plots.

##See `set walls`, `set grid vertical`.

#b `set table separator {tab|comma|"char"}` can be used to create csv files.

##See `plot with table`.

#b New options `set view projection {xy|xz|yz}` adjust view angles, axis tic

##and label placement to generate a 2D projection of a 3D splot.

##`set view projection xy` is equivalent to `set view map`.

#b `set rgbmax <value>` controls interpretation of input RGB values.

#b Array size can be implicit if an initializer is present, e.g. `Array A = [1,2,3]`.

#b Optional radial clipping of line segments in polar mode. See `set clip`.

#b Extra lines to customize the key can be added by substituting `keyentry` in

## place of a filename or function in `plot` and `splot` commands.

##This produces a line in the key without generating a corresponding plot.

##See `keyentry`.

#b User-specified translation of mouse coordinates (EXPERIMENTAL).

##See map_projection demo.

#b The `load` command can input commands from a datablock as an alternative to

## reading them from a file.

#b `set datafile columnheaders` causes first line of input to be read as strings

## rather than as data values. Equivalent to `set key autotitle columnheader`

## except that it does not affect generation of key entries. If this option is

## in effect the `stats` command will generate an array of strings containing

## the column headers found.

#end

4 New terminals and terminal options

#start

#b The `pcl5` terminal has been extended to support PCL5e/PCL5c printers and

## many modern gnuplot features.

#b The `pstricks` terminal has been extended to support many modern gnuplot

## features including RGB colors and transparency, filled polygons, and boxes.

#b New terminal `pict2e` to use the LaTeX2e pict2e environment.

## It directly supersedes older terminals `latex`, `emtex`, `eepic`, and `tpic`,

## which are no longer built by default.

#b The `texdraw` terminal has been extended to support text at arbitrary angles,

## variable line width, v5 dashed lines, and filled boxes and polygons. It can

## now be used with plain TeX, too. It still does not support color.

#b The previously experimental Direct2D variant of the `windows` terminal

## replaces the GDI and GDI+ variants. It now supports printing using D2D

## and color fonts.

#b The `dospc` and `svga` DOS terminals have been modernized and now support

## interactive keyboard and mouse (svga only) input.

#end

4 Pixmaps as objects

#start

#b `set pixmap` allows import of an image in standard format (png jpeg gif) as

## a pixmap that can be positioned anywhere in a plot or on the page.

## Unlike plotting `with image`, pixmap objects retain their original aspect

## ratio and size independent of axis scaling or rotation. See `pixmap`.

#end

4 Other new features

#start

#b Enhanced text mode accepts \U+xxxx (xxxx is a 4 or 5 character hexadecimal)

##as representing a Unicode code point that is converted to the corresponding

##UTF-8 byte sequence on output.

#end

4 Changes

#start

#b `pm3d filled area quadrangles` are clipped smoothly to current zrange.

## This affects pm3d surfaces and also the faces of 3D boxes, polygons, etc.

#b Revised syntax for plot style 'with parallelaxes'. See `parallel`.

## The histogram, parallelaxis, and spiderplot styles now use similar syntax

## that can iterate over plot elements:

## `plot for [column=1:N] DATA using column`

#b Imaginary values returned by the using specifier of a 2D plot are treated as

##undefined values (NaN) rather than as real(value). This was always true for

##function plots and 3D data plots. E.g. the following two plots are equivalent.

##plot [-1:1] sqrt(x); plot [-1:1] '+' using 1:(sqrt($1)

#b The `set fontpath` command is deprecated. The search path for fonts to be

## embedded in output from the postscript terminal has been revised.

#end

3 Features introduced in version 5.2

4 New plot styles and style options

#start

#b 3D plot style `with zerrorfill`. See `zerrorfill`, `fenceplots` and

^ <a href="http://gnuplot.info/demo_5.2/zerror.html">

zerror demo.

^ </a>

#b Beeswarm plots. See `set jitter`, `beeswarm` and

^ <a href="http://gnuplot.info/demo_5.2/jitter.html">

beeswarm plot demo

^ </a>

#b The symbol used for individual points in a plot can be controlled by data values

## (see `pointtype variable`)

#end

4 New data pre-processing filters

#start

#b Normalized frequency of occurrence in a data set (see `smooth fnormal`)

#b Automated binning of data (see `bins`)

#end

4 Polar mode improvements and extensions

#start

#b Polar coordinates may be used in label, arrow, and object definitions

#b `set [m]ttics` places ticmarks and labels on the perimeter of a polar plot. See

^ <a href="http://gnuplot.info/demo_5.2/ttics.html"> polar axis and ticlabels demo

^ </a>

#b `set rlabel` places a label above the r axis

#b Inverted `rrange` (i.e. set rrange [90:0]) allows use of celestial horizontal

## coordinates. See

^ <a href="http://gnuplot.info/demo_5.2/solar_path.html"> solar path demo

^ </a>

#b `set border polar` draws a solid line around the perimeter of a polar plot

#b `set theta` controls the position of theta = 0 around the perimeter of a

## polar plot and the sense (clockwise or anti-clockwise) of increasing theta

#end

4 Nonlinear coordinates systems

#start

#b Any plot axis can be assigned a pair of functions, possibly nonlinear, that

## describe the forward and reverse mapping to a linear range (see `set nonlinear`)

^ <a href="http://gnuplot.info/demo_5.2/nonlinear3.html">

Nonlinear x/y axis demo

^ </a>

#b The familiar command `set logscale` has been reimplemented as a special case

## nonlinear axis where the paired functions are log(x) and exp(x).

#end

4 New commands and command options

#start

#b Inside the bracketed clause of an iteration, `continue` jumps immediately

## to the next iteration, `break` immediately exits from the iteration

#b `toggle {<plotno> | "plottitle" | all}"` interactively enables or disables

## display of one element of the current plot (see `toggle`)

#b `save fit` replaces deprecated command `update`

#b `set table "outfile.name" append` will append subsequent tabulated plots to

## an existing text file rather replacing its contents

#b `set pm3d lighting` describes a lighting model with specular highlighting

## (see `lighting`)

#b `set minussign` tells gnuplot to use a special symbol in the current

## encoding to replace the ascii character '-' in negative numbers

#b `set micro` tells gnuplot to use a special symbol in the current encoding to

## replace the ascii character 'u' for the scientific notation prefix "micro"

## The special typographic symbols for micro and minussign are used only in axis

## tic labels and strings explicitly created with gprintf(). The byte sequence

## used to represent these characters depends on the current encoding.

#end

4 New data type "array"

#start

#b This gnuplot version introduces a new data type `array name[size]`.

## An array must be declared before use. Each array element A[i] may be a string,

## an integer, a real number, or a complex value. A single array may contain

## elements with different types. The cardinality operator |A| returns the size

## of array A. See `arrays`.

#end

4 New terminals and terminal options

#start

#b See `sixelgd` for description of a new terminal that supports interleaving

## plots with the command lines that generated them if gnuplot is run inside a

## vt340-compatible terminal emulator

#b The `domterm` terminal supports interleaving plots with the command lines

## that generated them if gnuplot is run inside an svg-aware terminal emulator

#b The `windows` terminal supports saving the current graph to a bitmap file

#b The `windows` terminal graph window can be docked to the wgnuplot text window

#b New (experimental) Direct2D/DirectWrite backend for the `windows` terminal

#b The `wxt` terminal supports exporting to an EMF file or printer on Windows

#b The `dumb` terminal supports ANSI colors for lines and fill area

#b The `tkcanvas` terminal has been rewritten to support many more modern gnuplot

## features, as well as new languages. (Since 5.0.3)

#end

4 Other new features

#start

#b An additional rotation angle `azimuth` affects the orientation of 3D plots.

## This can be set from the command line (see `set view azimuth`) or by dragging

## with the right mouse button. Hotkey `z` resets azimuth to 0.

#b gnuplot running under Windows can interpret Unicode (BMP) input scripts by

## converting them to the current encoding from `set encoding`, including UTF-8

#b Textboxes can be assigned a border color and fill color (see `set style textbox`)

#b Customized plot legends (see `plot title`, `set key`, `multiple keys`)

#b A sampling range specifier for plotting with pseudofile '+' can include a

## sampling interval. For example:

## plot sample [t=0:100:10] '+' using (t):(1):(label[t]) with labels

#b Pseudo-file '++' generates samples on the u and v axes, rather than x and y.

## This allows placement of multiple parametric surfaces in 3D that occupy

## distinct regions of Cartesian space. See `sampling.dem`.

#b new formats descriptors tH tM tS handle relative times (interval lengths).

##See `time_specifiers`.

#b ^R initiates a reverse-search through the history for the built-in readline

## which is used on Windows, too, see `command-line-editing`.

#b Revised printing support on Windows using `set output "PRN"`,

## see `windows printing`.

#end

3 Features introduced in version 5.0

?Features introduced in version 5.0

#start

#b The dot-dash pattern of a line can now be specified independent of other

## line properties. See `dashtype`, `set dashtype`, `set linetype`

#b The default sequence of colors used for successive elements in a plot is

## more easily distinguished by users with color-vision defects.

## The color sequence is under user control (see `set colorsequence`).

## This mechanism can also be used to generate monochrome plots

## (see `set monochrome`). In previous gnuplot versions `monochrome` could only

## be selected when changing the current terminal via `set terminal`.

#b New plot styles `with parallelaxes`, `with table`, and labeled contours.

#b New data pre-processing filter for monotonic cubic splines (see `smooth mcsplines`)

#b Text markup now supports bold and italic font settings in addition to

## subscript, superscript, font size and other previously available properties.

## Enhanced text mode is now enabled by default. See `enhanced text`.

## Text elements can be enclosed in a box (see `set style textbox`).

#b Interactive terminals support hypertext labels that only appear when the

## mouse hovers over the label's anchor point.

#b New coordinate system (Degrees, Minutes, Seconds). See `set xtics geographic`.

#b The default format for axis labels is "% h" ("$%h$" for LaTeX terminals).

## This format is like the C standard format %g except that the exponential term,

## if present, is written using a superscript. E.g. 1.2 x 10^5 rather than 1.2E05.

#b Support for 32-bit Alpha channel + RGB color #AARRGGBB. See `colorspec`.

#b Support for HSV color space via a translation function hsv2rgb(H,S,V).

#b Secondary axes (x2, y2) may be locked to the primary axis via a mapping

## function. In the simplest case this guarantees that the primary and secondary

## axis ranges are identical. In the general case it allows you to define a

## non-linear axis, something that previously was possible only for log scaling.

## See `set link`.

#b Each function in a plot command may optionally be preceded by a sampling

## range. This does not affect the overall range of the plot, only the range

## over which this function is sampled. See `plot` and `piecewise.dem`.

#b If the external library libcerf is available, it is used to provide complex

## math routines cerf, cdawson, erfi, faddeeva, and the Voigt profile

## VP(x,sigma,gamma).

#b The `import` command attaches a user-defined function name to a function

## provided by an external shared object (support is operating-system dependent).

## A template header and example source and make files for creating a suitable

## external shared object are provided in the demo collection.

#b Previous commands in the history list of an interactive session can be

## reexecuted by number. For example, `history !5` will reexecute the command

## numbered 5 in the `history` list.

#b Bit-shift operators >> and <<.

#b Shell invocation of gnuplot can pass parameters to a gnuplot script.

## gnuplot -c scriptfile.gp ARG1 ARG2 ARG3 ...

#end

2 Differences between versions 4 and 5

?changes

?differences

Some changes introduced in version 5 may cause certain scripts written

for earlier versions of gnuplot to behave differently.

* Revised handling of input data containing NaN, inconsistent number of data

columns, or other unexpected content. See Note under `missing` for examples

and figures.

* Time coordinates are stored internally as the number of seconds relative to

the standard unix epoch 1-Jan-1970. Earlier versions of gnuplot used a

different epoch internally (1-Jan-2000). This change resolves inconsistencies

introduced whenever time in seconds was generated externally. The epoch

convention used by a particular gnuplot installation can be determined using

the command `print strftime("%F",0)`. Time is now stored to at least

millisecond precision.

* The function `timecolumn(N,"timeformat")` now has 2 parameters. Because the

new second parameter is not associated with any particular data axis, this

allows using the `timecolumn` function to read time data for reasons other than

specifying the x or y coordinate. This functionality replaces the command

sequence `set xdata time; set timefmt "timeformat"`. It allows combining time

data read from multiple files with different formats within a single plot.

* The `reverse` keyword of the `set [axis]range` command affects only

autoscaling. It does not invert or otherwise alter the meaning of a command

such as `set xrange [0:1]`. If you want to reverse the direction of the

x axis in such a case, say instead `set xrange [1:0]`.

* The `call` command is provides a set of variables ARGC, ARG0, ..., ARG9.

ARG0 holds the name of the script file being executed. ARG1 to ARG9 are string

variables and thus may either be referenced directly or expanded as macros,

e.g. @ARG1. The contents of ARG0 ... ARG9 may alternatively be accessed as

array elements ARGV[0] ... ARGV[ARGC]. An older gnuplot convention of

referencing call parameters as tokens $0 ... $9 is deprecated in version 5.

* The optional bandwidth for the kernel density smoothing option is taken from

a keyword rather than a data column. See `smooth kdensity`.

2 Deprecated syntax

?deprecated syntax

?backwards compatibility

?compatibility

Gnuplot version 4 deprecated certain syntax used in earlier versions but

provided a configuration option that allowed backward compatibility.

Support for the old syntax has now been removed.

Deprecated in version 4 and removed in version 5:

set title "Old" 0,-1

set data linespoints

plot 'file' thru f(x)

plot 1 2 4 # horizontal line at y=1

update

Current equivalent:

TITLE = "New"

set title TITLE offset char 0, char -1

set style data linespoints

plot 'file' using 1:(f(column(2)))

plot 1 linetype 2 pointtype 4

save fit "filename"

Deprecated in version 5

if (defined(VARNAME)) ...

set style increment user

call 'script' 1.23 ABC

(in script: print $0, "$1", "number of args = $#")

set fontpath

set clabel

fit control variables FIT_*

Current equivalent:

if (exists("VARNAME")) ...

set linetype

call 'script' 1.23 "ABC"

(in script: print ARG1, ARG2, "number of args = ", ARGC

set cntrlabel

set fit <option> <value>

Deprecated in version 5.4

# use of a file containing `reread` to perform iteration

N = 0; load "file-containing-reread";

file content:

N = N+1

plot func(N,x)

pause -1

if (N<5) reread

Current equivalent

do for [N=1:5] {

plot func(N, x)

pause -1

}

2 Demos and Online Examples

?demos

?online examples

?examples

The `gnuplot` distribution contains a collection of examples in the `demo`

directory. You can browse on-line versions of these examples produced by the

png, svg, and canvas terminals at

^ <a href="http://gnuplot.info/demos/">

http://gnuplot.info/demos

^ </a>

The commands that produced each demo plot are shown next to the plot, and

the corresponding gnuplot script can be downloaded to serve as a model for

generating similar plots.

2 Batch/Interactive Operation

?batch/interactive

`Gnuplot` may be executed in either batch or interactive modes, and the two

may even be mixed together on many systems.

Any command-line arguments are assumed to be either program options

(see command-line-options) or names of files containing `gnuplot` commands.

Each file or command string will be executed in the order specified.

The special filename "-" is indicates that commands are to be read from stdin.

`Gnuplot` exits after the last file is processed. If no load files and no

command strings are specified, `gnuplot` accepts interactive input from stdin.

3 command line options

?command-line-options

?batch/interactive command-line-options

Gnuplot accepts the following options on the command line

-V, --version

-h, --help

-p, --persist

-d, --default-settings

-s, --slow

-e "command1; command2; ..."

-c scriptfile ARG1 ARG2 ...

-p tells the program not to close any remaining interactive plot windows

when the program exits.

-d tells the program not to execute any private or system initialization

(see `initialization`).

-s tells the program to wait for slow font initialization on startup.

Otherwise it prints an error and continues with bad font metrics.

-e "command" tells gnuplot to execute that single command before continuing.

-c is equivalent to -e "call scriptfile ARG1 ARG2 ...". See `call`.

3 Examples

?batch/interactive examples

To launch an interactive session:

gnuplot

To launch a batch session using two command files "input1" and "input2":

gnuplot input1 input2

To launch an interactive session after an initialization file "header" and

followed by another command file "trailer":

gnuplot header - trailer

To give `gnuplot` commands directly in the command line, using the "-persist"

option so that the plot remains on the screen afterwards:

gnuplot -persist -e "set title 'Sine curve'; plot sin(x)"

To set user-defined variables a and s prior to executing commands from a file:

gnuplot -e "a=2; s='file.png'" input.gpl

2 Canvas size

?canvas size

?canvas

?set term size

This documentation uses the term "canvas" to mean the full drawing area

available for positioning the plot and associated elements like labels,

titles, key, etc. NB: For information about the HTML5 canvas terminal

see `set term canvas`.

In early versions of gnuplot, some terminal types used the values from

`set size` to control also the size of the output canvas; others did not.

The use of 'set size' for this purpose was deprecated in version 4.

Almost all terminals now behave as follows:

`set term <terminal_type> size <XX>, <YY>` controls the size of the output

file, or "canvas". By default, the plot will fill this canvas.

`set size <XX>, <YY>` scales the plot itself relative to the size of the

canvas. Scale values less than 1 will cause the plot to not fill the entire

canvas. Scale values larger than 1 will cause only a portion of the plot to

fit on the canvas. Please be aware that setting scale values larger than 1

may cause problems.

Example:

set size 0.5, 0.5

set term png size 600, 400

set output "figure.png"

plot "data" with lines

These commands produce an output file "figure.png" that is 600 pixels wide

and 400 pixels tall. The plot will fill the lower left quarter of this canvas.

2 Command-line-editing

?line-editing

?editing

?command-line-editing

Command-line editing and command history are supported using either an

external gnu readline library, an external BSD libedit library, or a

built-in equivalent. This choice is a configuration option at the time

gnuplot is built.

The editing commands of the built-in version are given below. Please note that

the action of the DEL key is system-dependent. The gnu readline and BSD libedit

libraries have their own documentation.

@start table - first is interactive cleartext form

`Line-editing`:

^B moves back a single character.

^F moves forward a single character.

^A moves to the beginning of the line.

^E moves to the end of the line.

^H deletes the previous character.

DEL deletes the current character.

^D deletes current character, sends EOF if the line is empty.

^K deletes from current position to the end of line.

^L redraws line in case it gets trashed.

^U deletes the entire line.

^W deletes previous word.

^V inhibits the interpretation of the following key as editing command.

TAB performs filename-completion.

`History`:

^P moves back through history.

^N moves forward through history.

^R starts a backward-search.

#\begin{tabular}{|cl|} \hline

#\multicolumn{2}{|c|}{Command-line Editing Commands} \\ \hline \hline

#Character & Function \\ \hline

# & \multicolumn{1}{|c|}{Line Editing}\\ \cline{2-2}

#\verb~^B~ & move back a single character.\\

#\verb~^F~ & move forward a single character.\\

#\verb~^A~ & move to the beginning of the line.\\

#\verb~^E~ & move to the end of the line.\\