05/08/2018, 08:56 PM
(This post was last modified: 05/08/2018, 09:13 PM by Xorter.

*Edit Reason: edit2: new formula*)
Hi, again!

I would like to algoritmize the fractional derivatives and integrals, but here are some problems.

This is my code:

So e. g. D^2.5 x^2.5 = gamma(2.5-1) = Stein(x^2.5,2.5,0,1000.0), but it returns with this error message:

domain error in gpow [irrational exponent]: valuation != 0

Furthermore my Stein function return with ~0 in other cases. Why?

EDIT:

Here is the original formula:

https://wikimedia.org/api/rest_v1/media/...cc722c1f49

Oops, it looks I forgot some things from the my algorithm. It will be checked soon.

EDIT2:

Here is the new algorithm which is not working, too:

I would like to algoritmize the fractional derivatives and integrals, but here are some problems.

This is my code:

Code:

`int1(f,a,b,h)={return(sum(k=floor(min(a*h,b*h)),ceil(max(a*h,b*h)),sign(b-a)*subst(f,x,k/h)/h));}`

Stein(f,n,a,h)={return(der1(int1(f,0,a,h),a,h)/gamma(1-n));}

So e. g. D^2.5 x^2.5 = gamma(2.5-1) = Stein(x^2.5,2.5,0,1000.0), but it returns with this error message:

domain error in gpow [irrational exponent]: valuation != 0

Furthermore my Stein function return with ~0 in other cases. Why?

EDIT:

Here is the original formula:

https://wikimedia.org/api/rest_v1/media/...cc722c1f49

Oops, it looks I forgot some things from the my algorithm. It will be checked soon.

EDIT2:

Here is the new algorithm which is not working, too:

Code:

`Stein(f,n,a,h)={return(der1(int1(subst(f,x,u)/(x-u)^n,0,a,h),a,h)/gamma(1-n));}`

Xorter Unizo