uniform matrix

Example commands for plotting uniform matrix data:

     splot 'file' matrix using 1:2:3          # text input
     splot 'file' binary general using 1:2:3  # binary input

In a uniform grid matrix the z-values are read in a row at a time, i. e.,

    z11 z12 z13 z14 ...
    z21 z22 z23 z24 ...
    z31 z32 z33 z34 ...

and so forth.

For text input, if the first row contains column labels rather than data, use the additional keyword columnheaders. Similarly if the first field in each row contains a label rather than data, use the additional keyword rowheaders. Here is an example that uses both:

    $DATA << EOD
    xxx A   B   C   D
    aa  z11 z12 z13 z14
    bb  z21 z22 z23 z24
    cc  z31 z32 z33 z34
    EOD
    plot $DATA matrix columnheaders rowheaders with image

For text input, a blank line or comment line ends the matrix, and starts a new data block. You can select among the data blocks in a file by the index option to the splot command, as usual. The columnheaders option, if present, is applied only to the first data block.