FreeMat: FWRITE File Write Function

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FWRITE File Write Function

Section: Input/Ouput Functions

# Usage

Writes an array to a given file handle as a block of binary (raw) data. The general use of the function is

      n = fwrite(handle,A)

The `handle` argument must be a valid value returned by the fopen function, and accessable for writing. The array `A` is written to the file a column at a time. The form of the output data depends on (and is inferred from) the precision of the array `A`. If the write fails (because we ran out of disk space, etc.) then an error is returned. The output `n` indicates the number of elements successfully written.

Note that unlike MATLAB, FreeMat 4 does not default to `uint8` for writing arrays to files. Alternately, the type of the data to be written to the file can be specified with the syntax

      n = fwrite(handle,A,type)

where `type` is one of the following legal values:

- 'uint8','uchar','unsigned char' for an unsigned, 8-bit integer.
- 'int8','char','integer*1' for a signed, 8-bit integer.
- 'uint16','unsigned short' for an unsigned, 16-bit integer.
- 'int16','short','integer*2' for a signed, 16-bit integer.
- 'uint32','unsigned int' for an unsigned, 32-bit integer.
- 'int32','int','integer*4' for a signed, 32-bit integer.
- 'single','float32','float','real*4' for a 32-bit floating point.
- 'double','float64','real*8' for a 64-bit floating point.

# Example

Heres an example of writing an array of `512 x 512` Gaussian-distributed `float` random variables, and then writing them to a file called `test.dat`.

    --> A = float(randn(512));
    --> fp = fopen('test.dat','w');
    --> fwrite(fp,A,'single');
    --> fclose(fp);