Fixed-point multiplication with "altmult_complex" megafunction

If I understand well you have:

dataa on 16 bit in 2's complement fractional bit.

Your maximum dataa value is:

.0111_1111_1111_1111 = 0.25 - 2^(-16) = MaxA

Your minimum dataa value is:

.1000_0000_0000_0000 = -0.5 = MinA

datab on 16 bit unsigned with 14 fractional bit.

Your maximum dataa value is:

11.11_1111_1111_1111 = 4 - 2^(-14) = MaxB

Your minimum dataa value is:

00.00_0000_0000_0000 = 0 = MinB

Now you need to calculate the range of your output.

The maximum value is:

2*MaxA*MaxB = 2 - something small

The minimum value is:

-2 + something small

I guess that your output mustb be 2's complement with 2 integer bit and 14 fractional bit whose range is:

10.00_0000_0000_0000 = -2

01.11_1111_1111_1111 = 2 - 2^(-14)

Please check if my calculations are correct. I made them very fast.

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