gnuplot 命令详解
|
选择喜欢的代码风格
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
gnuplot 命令是一个便携式命令行驱动的图形实用程序，适用于 Linux、OS/2、MS Windows、OSX、VMS 和许多其他平台。源代码受版权保护，但可以自由分发（即，您不必为此付费）。它最初是为允许科学家和学生以交互方式可视化数学函数和数据而创建的，但现在已发展为支持许多非交互式用途，例如 Web 脚本。它也被 Octave 等第三方应用程序用作绘图引擎。自 1986 年以来，Gnuplot 就得到了支持并正在积极发展中。
gnuplot 命令安装：
-bash/zsh: gnuplot command not found #Debian apt-get install gnuplot #Ubuntu apt-get install gnuplot #Alpine apk add gnuplot #Arch Linux pacman -S gnuplot #Kali Linux apt-get install gnuplot #CentOS yum install gnuplot #Fedora dnf install gnuplot #OS X brew install gnuplot #Raspbian apt-get install gnuplot #Docker docker run cmd.cat/gnuplot gnuplot
gnuplot 命令补充说明：
gnuplot 是一个交互式绘图程序。如果在命令行上指定了文件名，则 gnuplot 会加载并执行每个文件均以指定的顺序进行，并在最后一个文件停止。如果未提供任何文件，则 gnuplot 会提示您输入交互式命令。
gnuplot 命令语法：
gnuplot [X11 options] [options] [file ...]
gnuplot 命令选项：
-p, --persist lets plot windows survive after main gnuplot program exits. -c scriptname ARG1 ARG2 ..., load script using gnuplot's "call" mecha-nism and pass it the remainder of the command line as arguments -d, --default settings. Do not read from gnuplotrc or ~/.gnuplot on entry. -e "command list" executes the requested commands before loading the next input file. -h, --help 打印帮助信息 -V 查看当前版本
gnuplot 命令实例：
启动 gnuplot 交互式图形绘图外壳：
gnuplot
gnuplot 绘制指定图形定义文件的图形：
gnuplot path/to/definition.plt
gnuplot 在加载定义文件之前通过执行命令来设置输出格式：
gnuplot -e "set output "path/to/filename.png" size 1024,768" path/to/definition.plt
在 gnuplot 退出后，保留图形图预览窗口：
gnuplot --persist path/to/definition.plt
gnuplot 脚本示例及效果图：
gnuplot - 生成的图片
# This file demonstrates
# -1- saving contour lines as a gnuplottable datablock
# -2- plotting a vector field on the same graph
# -3- manipulating columns using the '$1,$2' syntax.
# the example is taken here from Physics is the display of equipotential
# lines and electrostatic field for a dipole (+q,-q)
print "\n This file demonstrates"
print " -1- saving contour lines as a gnuplottable datablock"
print " -2- plotting a vector field on the same graph"
print " -3- manipulating columns using the '$1,$2' syntax."
print " the example is taken here from Physics is the display of equipotential"
print " lines and electrostatic field for a dipole (+q,-q)"
#
r(x,y)=sqrt(x*x+y*y)
v1(x,y)= q1/(r((x-x0),y))
v2(x,y)= q2/(r((x+x0),y))
#
vtot(x,y)=v1(x,y)+v2(x,y)
#
e1x(x,y)= q1*(x-x0)/r(x-x0,y)**3
e1y(x,y)= q1*(y)/r(x-x0,y)**3
e2x(x,y)= q2*(x+x0)/r(x+x0,y)**3
e2y(x,y)= q2*(y)/r(x+x0,y)**3
etotx(x,y)=e1x(x,y)+e2x(x,y)
etoty(x,y)=e1y(x,y)+e2y(x,y)
enorm(x,y)=sqrt(etotx(x,y)*etotx(x,y)+etoty(x,y)*etoty(x,y))
dx1(x,y)=coef*etotx(x,y)/enorm(x,y)
dy1(x,y)=coef*etoty(x,y)/enorm(x,y)
dx2(x,y)=coef*etotx(x,y)
dy2(x,y)=coef*etoty(x,y)
#
coef=.7
x0=1.
q1=1
q2=-1
xmin=-10.
xmax=10.
ymin=-10.
ymax=10.
#
unset autoscale
set xr [xmin:xmax]
set yr [ymin:ymax]
set isosam 31,31
#set view 0, 0, 1, 1
set view map
unset surface
set contour base
set cntrparam order 4
set cntrparam linear
set cntrparam levels discrete -3,-2 ,-1 ,-0.5 ,-0.2 ,-0.1 ,-0.05 ,-0.02 ,0 ,0.02 ,0.05 ,0.1 ,0.2 ,0.5 ,1 ,2 ,3
set cntrparam points 5
#
set label "-q" at -1,0 center
set label "+q" at 1,0 center
splot vtot(x,y) w l
print "Now create a in-memory datablock with equipotential lines"