Integrating a function with nested functions

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TheBestTreeInTheForest 2015-4-21

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https://ww2.mathworks.cn/matlabcentral/answers/212702-integrating-a-function-with-nested-functions

Hello all,

I have been stuck on a problem where I had written a function and integrated it in regards to 1 variable and it worked fine. I then adjusted it to become a function of 2 variables and changed to a double integral. However, this isn't working properly.

The original function was:

*function s_avg=siev_avg(rs,Mw,Jv)

rp=0;

fun1=@(rp)sieving(rs,rp,Mw,Jv).*log_normal(rp).*rp.^4;

fun2=@(rp)log_normal(rp).*rp.^4;

s_avg =integral(fun1,1.03*rs,inf)/integral(fun2,0,inf);

end*

I then changed it to this:

*function Sa=actual(rs,Mw)

b=0.03648*10^9;

fun1=@(r,rp)sieving3(rs,rp,Mw,r).*log_normal(rp).*rp.^4;

fun2=@(rp)log_normal(rp).*rp.^4;

Sa =integral2(fun1,0,b,1.03*rs,inf)./integral(fun2,0,inf);

end*

And the result was that instead of the integration running on the nested function I simply get the result from before multiplied by "b" which is the maximum value of "r".

How can I get this to run the integral on the innermost function because there is basically only one function nested 3 or 4 layers deep that is actually a function of "r".

Any input would be appreciated.

Thanks.