I’m trying to speed up a recursive calculation that is currently using a for-loop. A minimum working example is below. There are two computations in the recursion: "pn0" and "fact". I have figured out how to do fact out side the loop, but pn0 is giving me trouble. Any insight into how to remove the loop and/or speed this up would be greatly appreaciated! I have tried building up a separate function and using arrayfun, but that is calling a loop under the hood, so I don’t think it would be faster.
% define some constants
m = 0:10;
y = cos(pi/4);

% compute fact without a loop
fact = cumsum([1 ones(1,size(m,2)).*2]);
fact = fact(1:end-1);

% Generate the correct pn0 array
pn0 = 1; % initial value
factdum = 1; % initial value
pn_out = [];
fact_out = [];
for mm = 0:10
pn0 = -pn0*factdum*y; % do the computation <– this is the computation I’m trying to pull out of the loop
pn_out = [pn_out,pn0]; % store the pn0 array output
fact_out = [fact_out,factdum]; % store the fact array output
factdum = factdum + 2; % compute fact inside the loop to make sure it was done correctly outside the loop.
endI’m trying to speed up a recursive calculation that is currently using a for-loop. A minimum working example is below. There are two computations in the recursion: "pn0" and "fact". I have figured out how to do fact out side the loop, but pn0 is giving me trouble. Any insight into how to remove the loop and/or speed this up would be greatly appreaciated! I have tried building up a separate function and using arrayfun, but that is calling a loop under the hood, so I don’t think it would be faster.
% define some constants
m = 0:10;
y = cos(pi/4);

% compute fact without a loop
fact = cumsum([1 ones(1,size(m,2)).*2]);
fact = fact(1:end-1);

% Generate the correct pn0 array
pn0 = 1; % initial value
factdum = 1; % initial value
pn_out = [];
fact_out = [];
for mm = 0:10
pn0 = -pn0*factdum*y; % do the computation <– this is the computation I’m trying to pull out of the loop
pn_out = [pn_out,pn0]; % store the pn0 array output
fact_out = [fact_out,factdum]; % store the fact array output
factdum = factdum + 2; % compute fact inside the loop to make sure it was done correctly outside the loop.
end I’m trying to speed up a recursive calculation that is currently using a for-loop. A minimum working example is below. There are two computations in the recursion: "pn0" and "fact". I have figured out how to do fact out side the loop, but pn0 is giving me trouble. Any insight into how to remove the loop and/or speed this up would be greatly appreaciated! I have tried building up a separate function and using arrayfun, but that is calling a loop under the hood, so I don’t think it would be faster.
% define some constants
m = 0:10;
y = cos(pi/4);

% compute fact without a loop
fact = cumsum([1 ones(1,size(m,2)).*2]);
fact = fact(1:end-1);

% Generate the correct pn0 array
pn0 = 1; % initial value
factdum = 1; % initial value
pn_out = [];
fact_out = [];
for mm = 0:10
pn0 = -pn0*factdum*y; % do the computation <– this is the computation I’m trying to pull out of the loop
pn_out = [pn_out,pn0]; % store the pn0 array output
fact_out = [fact_out,factdum]; % store the fact array output
factdum = factdum + 2; % compute fact inside the loop to make sure it was done correctly outside the loop.
end recursion, eliminate for loop MATLAB Answers — New Questions

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