How to read each bit in a data of class "double"?

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Ivana 2012-9-19

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https://ww2.mathworks.cn/matlabcentral/answers/48531-how-to-read-each-bit-in-a-data-of-class-double

I am reading data that is being sent through the UDP protocol, with the function fread. I currently am reading a matrix with 19 elements. However, I want to read separately all the singular bits of the last element of the matrix. So is there a way I can chop the double precision of only the last element and read it in uint64? The matrix, say it's called A, has a size of [19 1], and if I use the conversion uint64(A(19)) it will only give me one number back. But I really need to read the singular bits... Any suggestions?

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Azzi Abdelmalek 2012-9-19

can you post a ample of your array

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Answer 1

Jan 2012-9-19

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https://ww2.mathworks.cn/matlabcentral/answers/48531-how-to-read-each-bit-in-a-data-of-class-double#answer_59295

编辑：Jan 2012-9-19

在 MATLAB Online 中打开

What about this:

firstPart = fread(fid, 18, 'double');
lastPart  = fread(fid, 1, 'uint64');

Or:

data = fread(fid, 19, 'double');
last = typecast(data(19), 'uint64');

Calling uint64(X) is equivalent to cast(X, 'uint64'). While this converts the type but keeps the value as exact as possible, TYPECAST does not change the bits.