Write and Read Fixed-Point Data
dsp.BinaryFileReader System objects do not support writing and reading fixed-point data. As a workaround, you can write the stored integer portion of the
fi data, read the data, and use this value to reconstruct the
Write the Fixed-Point Data
fi object to represent 100 signed random numbers with a word length of 14 and a fraction length of 12. Write the stored integer portion of the
fi object to the data file
myFile.dat. The built-in data type is
int16, which can be computed using
data = randn(100,1); fiDataWriter = fi(data,1,14,12); storeIntData = storedInteger(fiDataWriter); writer = dsp.BinaryFileWriter('myFile.dat'); writer(storeIntData);
Release the writer so that the reader can access the data.
Read the Fixed-Point Data
Specify the reader to read the stored integer data as
int16 data with 100 samples per data frame. The real-world value of the fixed-point number can be represented using . If you know the signedness, word length, and fraction length of the fixed-point data, you can reconstruct the
fi data using . In this example, the data is signed with a word length of 14 and a fraction length of 12.
reader = dsp.BinaryFileReader('Filename','myFile.dat',... 'SamplesPerFrame',100,... 'DataType','int16'); data = reader(); fractionLength = 12; wordLength = 14; realValue = 2^(-fractionLength)*double(data); fiDataReader = fi(realValue,1,... wordLength,fractionLength);
Verify that the writer data is the same as the reader data.
ans = logical 1