# Gaussian hypergeometric function Calculator

## Calculates Gaussian hypergeometric function | |||

- Purpose of use
- For checking an expression of the binomial-binomial convolution probability mass function. Used to tabulate some values (too much work to get my own implementation of the Gauss'' hypergeometric function for that simple purpose!)
- Comment/Request
- An option to avoid commas in the result would be appreciated (for direct copy-paste)

[1] 2018/05/25 01:14 Male / 40 years old level / An engineer / Very /

- Purpose of use
- research

[2] 2018/04/30 21:11 Male / 50 years old level / A teacher / A researcher / A little /

- Purpose of use
- Use WKB method to calculate eigenvalues of harmonic oscillator

[3] 2018/03/16 08:08 Female / 20 years old level / High-school/ University/ Grad student / Useful /

- Purpose of use
- Solve integral
- Comment/Request
- Your calculator is extremely helpful. Thank you!

Which series formula are you using for the hypergeometric fucntion 2F1(a,b;c;z) in case of z<0, but |z|>1, for example z=-2? - from Keisan
- We use "z -> z/z-1" and "z -> 1/z" convert formula in case of z<0 and |z|>1.

[4] 2017/09/11 13:59 Male / 40 years old level / An engineer / Very /

- Purpose of use
- Solve a integral problem via hypergeometric summation

[5] 2017/09/09 09:46 Male / 40 years old level / An engineer / Useful /

- Purpose of use
- Trying to write a code for computation of bessel function for complex argument. I will love to have the algorithm you implemented

[6] 2016/08/26 21:52 Male / 30 years old level / A teacher / A researcher / Very /

- Purpose of use
- to test my own implementation
- Bug report
- a=0.1; b=0.2; c=0.4; z=2

Keisan result: 1.956835345165 -0.4667180917933i

My result: 1.01537811446162-0.16082009437679i; not claiming it is 100% correct, just trying to implement this: http://arxiv.org/pdf/0708.0116v2.pdf

Proof of error:

Keisan (b=0.1999999999999999): 1.0153781144616367 -0.1608200943767892i

Keisan (b=0.2000000000000001): 1.0153781144616367 -0.1608200943767894i

Is there anything specific about 2F1 function around b=0.2? - from Keisan
- We fixed a bug about Gaussian hypergeometric function. Thank you for your advice.

[7] 2016/06/05 07:58 Male / 20 years old level / An office worker / A public employee / Very /

- Purpose of use
- Solve a integral problem via hypergeometric summation

[8] 2015/04/23 07:03 Male / 60 years old level or over / A retired people / Useful /

- Purpose of use
- Checking the stability range of 2F1 for complex z-values
- Comment/Request
- How do you enter z-complex=values on your Gaussian Hypergeometric calculator?

[9] 2015/04/22 03:11 Male / 60 years old level or over / Others / A little /

- Purpose of use
- Verify special implementation in own code

[10] 2015/02/25 02:17 Male / 30 years old level / A teacher / A researcher / Useful /

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