IQMath question

tathvamasi

HI,

Can someone tell me if using large number of nested IQ functions in a single line of C code can cause loss of precision in the final answer. I am experiencing such a problem where in I get the right answer if I split the operation in 3 lines of code, but a different answer if I combine the operations by nesting IQ functions.

Thanks in advance.

over 9 years ago

0 Gautam Iyer over 9 years ago

Guru 192875 points

Hi Jose,

Jose Titus said:
but a different answer if I combine the operations by nesting IQ functions.

Can you paste the combined line?

Regards,

Gautam

0 tathvamasi over 9 years ago in reply to Gautam Iyer

Prodigy 250 points

This is the line:

v.effd=_IQ21toIQ(_IQ21div( _IQtoIQ21(_IQmpy(v.K1 , _IQmpy(v.isdpu , _IQ(v.Ibase)))) , _IQ21mpy(_IQtoIQ21(_IQdiv(v.Vdc , _IQ(2))) , _IQ21(v.Vbase))));

0 Gautam Iyer over 9 years ago in reply to tathvamasi

Guru 192875 points

Yup, I've observed the same thing with complex equations.... not IQMath specifically.
I had to break it into multiple lines as you've done!
The only answer I've from my-side is... "It doesn't work that way!"

Regards,
Gautam

0 tathvamasi over 9 years ago in reply to Gautam Iyer

Prodigy 250 points

Thanks Gautam.

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