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Syntax

a = fread(fid)

a = fread(fid, n)

a = fread(fid, n, type)

a = fread(fid, n, type, s)

[a, b] = fread(fid)

[a, b] = fread(fid, n)

[a, b] = fread(fid, n, type)

[a, b] = fread(fid, n, type, s)

Description

Reads binary data from a file.

Examples

Inputs

Name	Description
fid	Specifies the identifier for the file you want to read. Use the fopen function to open a file and assign it an identifier. fid is an integer.
n	Specifies the amount of data to read from the file specified by fid. LabVIEW discards all but the first two elements of n. If n is inf, LabVIEW reads the file until it reads all the data or an error occurs. n is a 32-bit signed integer or a 1D matrix of those values.
type	Specifies the data type to read from the file specified by fid. If you specify s, you can add a positive integer of the form 'm*' before type. LabVIEW then skips s bytes after each m bytes it reads successfully. You also can add '=>' and a data type after type to specify the data type that LabVIEW returns. type is a string that accepts the following values. 'double' Reads 64-bit, double-precision, floating-point numbers. 'float32' Reads 32-bit, single-precision, floating-point numbers. 'float64' Reads 64-bit, double-precision, floating-point numbers. 'int16' Reads 16-bit signed integers. 'int32' Reads 32-bit signed integers. 'int64' Reads 64-bit signed integers. 'int8' Reads 8-bit signed integers. 'schar' Reads signed characters. 'single' Reads 32-bit, single-precision, floating-point numbers. 'uchar' (default) Reads unsigned characters. 'uint16' Reads 16-bit unsigned integers. 'uint32' Reads 32-bit unsigned integers. 'uint64' Reads 64-bit unsigned integers. 'uint8' Reads 8-bit unsigned integers.
s	Specifies the number of bytes to skip after each m bytes as you specify in type. s is a positive integer.

Outputs

Name	Description
a	Returns the data that LabVIEW read from the file specified by fid. a is a vector or matrix of 64-bit, double-precision, floating-point numbers.
b	Returns the amount of data that LabVIEW read successfully from the file specified by fid. b is a positive integer.

Examples

fid = fopen('test.dat', 'r');
[a, b] = fread(fid, [10, Inf], '10*int8=>int32', 5);
fclose(fid);

Related Topics

fclose
fopen
fseek
fwrite