It has been my experience that, with an appropriate choice of data structure and straightforward lines of code, Julia is better. The Julia realization will be fast enough .. for the operations you need 2x-3x C, once the loop executes, and it is much less hassle, and easier to maintain. There are ways to do it wrong, and incur uneeded overhead. I defer to others to give you specific guidance.
On Thursday, July 30, 2015 at 1:40:34 PM UTC-4, Forrest Curo wrote: > > I want to turn an unsigne64 into bytes, chew on the bytes, & rearrange > into a new unsigned64. > > Should I expect significant gain by reading it into a C function to make > it a union of char and unsigned64, take out the chars & put the new ones > back into that union -- > > or should it be close enough in speed to stay in julia, > with something like: > > for i = 1:8 > bites[i] = x & 255 > x >>= 8 > end > > [doing stuff to bites] > > x = 0 > for i = 1:8 > x += bites[i] > end > ? > >
