MATLAB is taking too much time to solve the following integral?

Hello all, I am trying to solve the following integral but MATLAB is taking too long to solve it.

---- (1)

where is lower incomplete Gamma function, x is variable of integration and all other things are constant.

Any help in this regard will be highly appreciated.

[chaaru datta]

I tried to write the MATLAB code for first lower incomplete Gamma function but got the following error: Limits of integration must be double or single scalars.

Here is the code that I had written:

G = @(x)((gam_s*(1+x)-1)/(A*sig2_fsnrn));
G1 = @(x) x/(A1*sig2_fsnen);
fun = @(t) t.^(1+d-1).*exp(-t);
low_gam = integral(fun,0,G);

Answer 1

[Dyuman Joshi]

integral is used for numerical integration of functions, not partial integrations. It expects numerical value for 2nd and 3rd input.

Check out gammainc to define lower incomplete gamma function.

[chaaru datta]

Thank you so much for your answer sir. But it gave the following error:

Inputs must be real, full, and double or single.

[Dyuman Joshi]

Can you show your code?

[chaaru datta]

for d = 0:1:10
    syms x; 
    G = ((gam_s*(1+x)-1)/(A*sig2_fsnrn));
    low_gam = gammainc(1+d,G);
end

%This is my code sir.

[chaaru datta]

Can we say there is no way to solve such integration.

[Torsten]

f = @(x) ...
P = integral(f,0,Inf)

So all you have to do is write down the formula for the function to be integrated.

I think you should accept that we will not do that for you.

Of course, you must give numerical values to all parameters involved except for x.

[chaaru datta]

I know this approach for integration sir. But I am getting confused as integration involves two lower incomplete gamma function which also needs use of integral command for its computation.

And if I use the command integral in case of lower incomplete gamma function then I get the error Limits of integration must be double or single scalars.

[Torsten]

The incomplete gamma function is a MATLAB function and can directly be called:

https://de.mathworks.com/help/matlab/ref/gammainc.html

[chaaru datta]

I know about this function also. However if I use it then it gives me the error : Inputs must be real, full, and double or single.

[chaaru datta]

Thank you so much @Torsten sir and @Dyuman Joshi sir. Its because of your suggestions, I could implement and plot the equation in MATLAB.