Read the matrix data from a text file. If not defined the separator between fields is determined from the file itself. Otherwise the separation character is defined by sep.
Given two scalar arguments r0 and c0, these define the starting row and column of the data to be read. These values are indexed from zero, such that the first row corresponds to an index of zero.
The range parameter must be a 4 element vector containing the upper left and lower right corner
[
R0,
C0,
R1,
C1]
or a spreadsheet style range such as 'A2..Q15'. The lowest index value is zero.