readb fortran file binary read

## Syntax

    x=readb(file-name,m,n [,rec])

## Arguments

file-name

  string or integer

m, n

  integers (dimensions of the matrix x). Set m=-1 if you do not know the numbers of rows, so all the file is read

rec

  vector of positive integers. the selected records for direct access. This vector size must be equal to the number of rows of desired `x`.

## Description

binary read of the matrix `x` in the file `file-name`. Matrix entries are supposed to have been stored on 8 byte words.

For direct record access, file must have been previously opened using `file` function to set the record_length. `file-name` must be the result of the `file` function.

## See also

- file
- write
- writb
- mget
- read4b