Is there any reason to think that sin and cos can be computed jointly more 
efficiently than computing each one independently?

> On Jul 28, 2014, at 12:21 AM, Ken Bastiaensen <[email protected]> 
> wrote:
> 
> Thank you for your answers. Yes, it seems sincos is slower than calling (sin, 
> cos) at the moment. 
> I don't know about libm standards, but if it's available in openlibm, why not 
> export it?
> 
> Ken
> 
> 
>> On Sun, Jul 27, 2014 at 8:26 PM, Viral Shah <[email protected]> wrote:
>> Is sincos a standard libm function?
>> 
>> Also, I wonder if creating the one entry array is too expensive, and if we 
>> should just call sin and cos separately. The vectorized version may be able 
>> to benefit from calling sincos directly.
>> 
>> -viral
>> 
>> 
>>> On Monday, July 28, 2014 1:02:06 AM UTC+5:30, Isaiah wrote:
>>> It doesn't appear to be wrapped, but you can call it yourself like this:
>>> 
>>> julia> sincos(x) = begin psin = Cdouble[0]; pcos = Cdouble[0]; 
>>> ccall(:sincos, Void, (Cdouble, Ptr{Cdouble}, Ptr{Cdouble}), x, psin, pcos); 
>>> (psin[1], pcos[1]); end
>>> sincos (generic function with 1 method)
>>> 
>>> julia> sincos(pi)
>>> (1.2246467991473532e-16,-1.0)
>>> 
>>> Feel free to open an issue or pull request if you think it should be 
>>> exported - might have just been an oversight.
>>> 
>>> 
>>>> On Sun, Jul 27, 2014 at 3:25 PM, Ken B <[email protected]> wrote:
>>>> Hi,
>>>> 
>>>> I want to calculated sine and cosine together of the same angle. I saw 
>>>> this function is implemented in openlibm, but is it available in julia and 
>>>> how?
>>>> 
>>>> https://github.com/JuliaLang/openlibm/blob/18f475de56ec7b478b9220a5f28eb9a23cb51d96/src/s_sincos.c
>>>> 
>>>> Thanks!
>>>> Ken
> 

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