Faster than for loop?
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I presently have this code which tests a paricular function which I created _ _ [y n] function_gen1pdf1(a,b,c) _ _ for N times. Now this works fine up to N=100. However, I want it to work for N=100,000 but it's taking much too long to compute. Is it possible to vectorize it or make it work faster? Any suggestions are much appreciated!
N=100000;
y=zeros(N,1);
n=zeros(N,1);
for i=1:N; %testing the function for 100000 times
[y(i) n(i)]= function_gen1pdf1(2,3,0.5); %The function being tested
end
7 个评论
Star Strider
2015-2-7
Please post the function code!
Stephen23
2015-2-7
"Is it possible to vectorize it": this depends entirely on the function function_gen1pdf1. If you want help trying to vectorize this, then you have to upload its code too.
Geoff Hayes
2015-2-7
rox - I don't understand the line
[y(i) n(i)]= function_gen1pdf1(2,3,0.5);
You keep calling function_gen1pdf1 with the same set of inputs for every i. Why is the code repeating the same call at every iteration of the for loop?
Tapan
2015-2-7
I will echo everyone else's comments - you need to provide the function code. Perhaps try a parlor loop in the meantime.
Jan
2015-2-7
@Geoff: The "gen" in the name might mean a genetic algorithm, such that random effects can be the reasn for different results inspite of the same inputs.
Image Analyst
2015-2-7
Or maybe it generates a PDF document, or generates a probability distribution function. Whatever it does, apparently PDF does not mean "Pretty Darn Fast".
采纳的回答
Image Analyst
2015-2-7
It's your function, it's not the for loop. If you just run a for loop 100,000 times it takes 0.2 milliseconds.
I tried it:
tic
for k = 1 : 100000
;
end
toc
Elapsed time is 0.000219 seconds.
So it if takes a long time, it's due to your function_gen1pdf1() function.
3 个评论
rox
2015-2-7
Image Analyst
2015-2-7
rox, you're welcome. Does that mean that you can now mark the answer as "Accepted"?
rox
2015-2-7
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