From J Wiki
Jump to: navigation, search
Plot | Verbs | Class Commands Data Options Outputs Types | Colors Fonts Keys Text YAxes | Function Multi Shape

Plot supports several outputs:

  • isigraph window (Only in J6, the default if not J console)
  • GTK window (the default for JGTK)
  • EPS file
  • PDF file (the default under J console in Mac and Windows)
  • HTML5 canvas element (the default for JHS)
  • Cairo graphic (png image file, the default under J console if supported)
  • QT window (the default for QT)
  • QTC (image file, requires QT addon but also works under jconsole)

The isigraph window may be printed, or copied to the clipboard, bmp or emf file.

Some outputs are only supported under a particular J release, see Plot/Commands for further details.


For EPS and PDF, Plot attempts to display the plot using the viewers defined in Edit|Configure|External Programs. For example, GSView can be used for both formats. If you use this, it is suggested that you include the -e option that enables a new image to be drawn in the same window. This means that you can experiment with drawing plots, each appearing in the same GSView window. For example, your configuration might be:

c:\program files\ghostgum\gsview\gsview32.exe -e

You can use Adobe Reader to read PDF files, but note that if a file is already open in Adobe, then you cannot write to it again. In this case, close the file in Adobe before re-running the plot.


The plot calculation is the same for all methods, except only when calculating font metrics. For a discussion of this, see Fonts, and in particular the discussion on fontscale.

Note that drawings to these outputs are made independently, so there may be minor differences between them. For example, one plot may display more ticmarks than another.

Typically, if you draw to outputs with the same number of units, e.g. the defaults of 480 x 360 pixels in isigraph, and 480 x 360 points in EPS and PDF, then your plots will be essentially the same. You may notice differences if you choose different sized outputs, since each plot is fitted to the space available.