MATLAB: To attempt and solve a problem. This is the code:

MATLAB

%pdb.m
function dydx = pdb(x,y)
dydx=(-2*x^3)+(12*x^2)-(20*x)+(8.5);
%runpdb.m
clear
clc
rentang_x = [0 4];
y0 = 1;
[x,y] = ode23('pdb',rentang_x,y0);
plot(x,y)
xlabel('x')
ylabel('y')
the error is 
Error using pdb (line 3)
Not enough input arguments.

Best Answer

How are you running your code?

That is a function that takes arguments, not a script, so you must call it from the command line (or another script/function/class) passing arguments into it as e.g.

pdb( 6, 7 );

rather than just clicking 'Run' on the .m file.

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MATLAB: Speeding up code: vectorization and others

Your code choked my computer. R2016a, no parallel toolbox, no mex. However, regarding the innermost loop

for m = -n:2:n
end

Move nn = n + 1; outside the loop. Helps a little bit (tic,toc).
Replace the three if-statements by a if-elseif-elseif-else-end. Again small effect. However, 30% faster when profiling.
Split the loop into two loops one with m<0 and one with m>0 and remove the if-statements. Note: odd and even n. Again small effect. However, when profiling the elapse time was cut in half.

Conclusion: The "JIT/Accelerator" don't need my help in these cases. However, the "JIT/Accelerator" is less effective together with the profiler.

MATLAB: GPU and CPU code: How to do

Depending on how your codes are structured, try to decide early on whether to use gpuArray or regular array. Most Matlab built-in functions will automatically determine and use gpuArrays.

See here https://www.mathworks.com/help/distcomp/run-matlab-functions-on-a-gpu.html

function Output = main(Input)
%Decide early to use gpuArray
if gpuDeviceCount > 0 
    Input = gpuArray(Input);
end
%Use functions that support either gpuArray or regular arrays as inputs
plot(Input) 
Input = myCustonFcn(Input) %custom function that allows gpuArray inputs
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if existsOnGPU(Input)
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Best Answer

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MATLAB: GPU and CPU code: How to do

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