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readHeader

Read file header

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Syntax

header = readHeader(reader)

Description

header = readHeader(reader) returns the header structure, header, from the file specified by the binary file reader, reader.

example

Examples

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Open Live Script

Read the header data from a binary file using the readHeader function.

Write a header, followed by the data to a binary file named myfile.dat. The header is a 1-by-4 matrix of double precision values, followed by a 5-by-1 vector of single-precision values. The data is a sequence of 1000 double-precision values.

fid = fopen('myfile.dat','w');
fwrite(fid,[1 2 3 4],'double');
fwrite(fid,single((1:5).'),'single');
fwrite(fid,(1:1000).','double');
fclose(fid);

Read the header using a dsp.BinaryFileReader object. Specify the expected header structure. This structure specifies only the format of the expected binary file header and does not contain the exact values.

reader = dsp.BinaryFileReader('myfile.dat');
s = struct('A',zeros(1,4),'B',ones(5,1,'single'));
reader.HeaderStructure = s;

Read the header using the readHeader function.

H = readHeader(reader);
fprintf('H.A: ')
H.A: 

fprintf('%d ',H.A);
1 2 3 4 

fprintf('\nH.A datatype: %s\n',class(H.A))
H.A datatype: double

fprintf('H.B: ')
H.B: 

fprintf('%d ',H.B);
1 2 3 4 5 

fprintf('\nH.B datatype: %s\n',class(H.B))
H.B datatype: single

Input Arguments

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Binary file reader object, specified as a dsp.BinaryFileReader System object.

Output Arguments

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Header structure of the binary file, returned as a structure. Each field of the structure is a real matrix of a built-in type. For example, if you specify the HeaderStructure property of the dsp.BinaryFileReader object to struct('field1',1:10,'field2',single(1)), the object writes a header formed by 10 double-precision values, (1:10), followed by one single precision value, single(1). If you do not specify a header, the object returns an empty structure, struct([]).

Data Types: struct

Version History

Introduced in R2016b

See Also

Objects