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[edit] 2D plots

plot(y)

If a single data argument is supplied, it is taken as the set of Y coordinates and the X coordinates are taken to be the indices of the elements, starting with 1.

plot(x, y)

• If the first argument is a vector and the second is a matrix, the vector is plotted versus the columns (or rows) of the matrix. (using whichever combination matches, with columns tried first.)
• If the first argument is a matrix and the second is a vector, the columns (or rows) of the matrix are plotted versus the vector. (using whichever combination matches, with columns tried first.)
• If both arguments are vectors, the elements of Y are plotted versus the elements of X.
• If both arguments are matrices, the columns of Y are plotted versus the columns of X. In this case, both matrices must have the same number of rows and columns and no attempt is made to transpose the arguments to make the number of rows match.

[edit] Example

x = linspace(0, 2*pi, 100);
y = sin(x);
plot(x, y);

[edit] Non-linear plots

semilogx, semilogy, loglog, polar

[edit] Formatting

    `-'
          Set lines plot style (default).

    `.'
          Set dots plot style.

    `@'
          Set points plot style.

    `-@'
          Set linespoints plot style.

    `^'
          Set impulses plot style.

    `L'
          Set steps plot style.

    `N'
          Interpreted as the plot color if N is an integer in the range
          1 to 6.

    `NM'
          If NM is a two digit integer and M is an integer in the range
          1 to 6, M is interpreted as the point style.  This is only
          valid in combination with the `@' or `-@' specifiers.

    `C'
          If C is one of `"r"', `"g"', `"b"', `"m"', `"c"', or `"w"',
          it is interpreted as the plot color (red, green, blue,
          magenta, cyan, or white).

    `";title;"'
          Here `"title"' is the label for the key.

    `+'
    `*'
    `o'
    `x'
          Used in combination with the points or linespoints styles,
          set the point style.

     The color line styles have the following meanings on terminals that
     support color.

          Number  Gnuplot colors  (lines)points style
            1       red                   *
            2       green                 +
            3       blue                  o
            4       magenta               x
            5       cyan                house
            6       brown            there exists

     The FMT argument can also be used to assign key titles.  To do so,
     include the desired title between semi-colons after the formatting
     sequence described above, e.g. "+3;Key Title;" Note that the last
     semi-colon is required and will generate an error if it is left
     out.

[edit] Commands related to plot

xlabel, ylabel, and title, replot

[edit] 3D plots

mesh, meshgrid, surf

[edit] Contour plots

contour

[edit] Images

colormap, image, imshow, hsv2rgb

[edit] Saving and printing graphs

Print a graph to a printer or save it to a file

print("-Pprinter")
print("filename", "-ddevice")

Devices:

         `ps'
         `ps2'
         `psc'
         `psc2'
               Postscript (level 1 and 2, mono and color)

         `eps'
         `eps2'
         `epsc'
         `epsc2'
               Encapsulated postscript (level 1 and 2, mono and color)

         `ill'
         `aifm'
               Adobe Illustrator

         `cdr'
         `corel'
               CorelDraw

         `hpgl'
               HP plotter language

         `fig'
               XFig

         `dxf'
               AutoCAD

         `mf'
               Metafont

         `png'
               Portable network graphics

         `pbm'
               PBMplus

If the device is omitted, it is inferred from the file extension, or if there is no filename it is sent to the printer as postscript.

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