Datafile can be in an ascii or binary matrix format. The `matrix` flag indicates that the file is ascii, the `binary` or `matrix binary` stands for a binary format. For details, see `matrix ascii` and `matrix binary`.
Basic usage in `splot`:
splot 'a.dat' matrix
splot 'a.gpbin' {matrix} binary
Advanced usage in `splot`:
splot 'a.dat' matrix using 1:2:3
splot 'a.gpbin' {matrix} binary using 1:2:3
allows to transform the axes coordinates and the z-data independently.
Usage in `plot`:
plot `a.dat` matrix
plot `a.dat` matrix using 1:3
plot 'a.gpbin' {matrix} binary using 1:3
will plot rows of the matrix, while using 2:3 will plot matrix columns, and using 1:2 the point coordinates (rather useless). Applying the every option you can specify explicit rows and columns.
Example – rescale axes of a matrix in an ascii file:
splot `a.dat` matrix using (1+$1):(1+$2*10):3
Example – plot the 3rd row of a matrix in an ascii file:
plot 'a.dat' matrix using 1:3 every 1:999:1:2
(rows are enumerated from 0, thus 2 instead of 3).