Hi Stefan,

sorry, yes, I had somehow overlooked fma. Mainly I was looking for an 
in-place version though, like fma! and muladd!. Is there a reason those 
don't exist?

On Saturday, July 23, 2016 at 7:50:30 PM UTC+2, Stefan Karpinski wrote:
>
> Yes: https://github.com/JuliaLang/julia/issues/6330. In short, there are 
> both fma and muladd operations with different purposes:
>
> help?> fma                                                                 
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> search: fma findmax @fastmath UniformScaling                               
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>   fma(x, y, z)                                                             
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>                          
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>                           
>   Computes x*y+z without rounding the intermediate result x*y. On some 
> systems this is significantly more expensive than x*y+z. fma is used to 
> improve accuracy in certain algorithms. See muladd.                         
>                                                                             
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> help?> muladd                                                             
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>                           
> search: muladd                                                             
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>   muladd(x, y, z)                                                         
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>                           
>                                                                           
>                                                                             
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>   Combined multiply-add, computes x*y+z in an efficient manner. This may 
> on some systems be equivalent to x*y+z, or to fma(x,y,z). muladd is used to 
> improve performance. See fma.
>
> On Sat, Jul 23, 2016 at 1:40 PM, Oliver Schulz <[email protected] 
> <javascript:>> wrote:
>
>> Does Julia have a standardized FMA (Fused-Multiply-Add) function? Like 
>> fma(A, B, factor) and fma!(dest, A, B, factor), so that that GPU libraries, 
>> etc. can provide optimized versions?
>>
>
>

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