Turn off rt_roundd inserted function

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Matthew on 22 Jul 2013
Edited: Stephen23 on 25 Apr 2017
During generating my C code I constantly get preparing to casting function. It's definition is:
static real_T rt_roundd(real_T u)
real_T y;
if (fabs(u) < 4.503599627370496E+15) {
if (u >= 0.5) {
y = floor(u + 0.5);
} else if (u > -0.5) {
y = 0.0;
} else {
y = ceil(u - 0.5);
} else {
y = u;
return y;
No matter what it does, it works horribly for my audio processing algorithm so I don't want it. How can I achieve it?
Removing it's calls works fine for my algorithm but I don't want to do it manually every time I get that code.
Matthew on 23 Jul 2013
I don't care. Audio samples become distorted after calculations in floating point and casting to C code and I'm not sure what causes that. Maybe it's Keil's compiler issue, maybe some optimalization I don't know.
What really works is removing all rt_roundd calls or putting "return y;" as first instruction in this function.

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Answers (1)

Ryan Livingston
Ryan Livingston on 23 Jul 2013
Edited: Ryan Livingston on 25 Apr 2017
You can use a Code Replacement library and define a function replacement for the round function. The library says map function foo to function bar in the generated code and math functions like ROUND are generally replaceable.
Here's a demo for using these libraries:
and general doc for creating them:


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