MATLAB: FI data type NOT operator

fixed point data type bitnotFixed-Point Designer

I am trying to take the BITNOT of an FI data type. For example if I have the following code:

tst = fi(5, numerictype(0,4,0));

How would I get the bitwise NOT of 5 (which should be hex A, or 10)? The ~ operator is the logical not, and is not what I need. I have searched the documentation, and maybe I missed it, but there does not seem to be anything in the BITWISE operators section. Am I just going nuts? Is the only way to do this do use a for loop with the BITSET/BITGET commands?

Thanks.

Best Answer

Maxval = fi(15, numerictype(0,4,0));
bitnot5 = bitxor(Maxval, tst);

I do not know why there is no specific bitnot(), but this is a common transformation, bitwise_not(value) = xor(all_ones, value)

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This enhancement has been incorporated in Release 2008a (R2008a). For previous product releases, read below for any possible workarounds:

The FI function is working as it is designed see the following example.

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To obtain the quantization that you are looking for, you should execute the following command:

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Which MATLAB processes as the following commands:

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Best Answer

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