In the most simple case, zimg reads ascii data, one data point per line, skipping blank lines and comment lines. Comment lines start with a '#' mark. If the input data size is not specified by the [--size] switch, zimg searches for the first two integers in the ascii file, even in comment lines. So a very simple example of a very simple two-dimensional data file would be:

# 2 2

1
1

2
2
        

Blank lines are optional and were used in this example to group the two file into 'rows' and 'columns' of the two-dimensional data. zimg would get the size of the data from the comment line

# 2 2

and then read 2 x 2 = 4 data items.

The previous example of 2 x 2 two-dimensional data isn't very illustrative. The following examples are made with sinc.dat, which contains 40 x 40 data points of a sinc function. The first line of sinc.dat contains the dimensions of the two-dimensional data:

# 40 40

zimg can generate a png image of sinc.dat by

# zimg sinc.dat

The result is show here:

The [--jpeg] switch is used to generate a jpeg instead of a png image.