Returns column number num from filename as a list.
Columns are separated by whitespace and are numbered left to right
beginning with 0.
atox specifies the string conversion function applied to the
column values.
Lines which are empty or begin with comment_char are ignored.
Returns filename as a matrix, lines corresponding to rows.
Every line of the file should have the same number of columns.
atox specifies the string conversion function applied to the
column values.
Lines which are empty or begin with comment_char are ignored.
Returns the lines of filename as a list of arrays.
Useful when lines have different number of columns.
atox specifies the string conversion function applied to the
column values.
Lines which are empty or begin with comment_char are ignored.