Message Boards Message Boards

0
|
2833 Views
|
5 Replies
|
5 Total Likes
View groups...
Share
Share this post:

Gamma function evaluation with arbitrary precision

Nicolas Legnazzi
Posted 2 years ago

Hello, I am a Physics student and I am trying to get values of incomplete Gamma function with arbitrary precision. On the Mathematica page they clarify that the Gamma function can be evaluated with arbitrary precision. I have the 11.1.1 version of Mathematica and I am entering the following code to evaluate with 64 digits:

N[Gamma[3.33, 10.14], 64]

However the result appears with 18 digits:

0.010989671959126465

Is there a way to get it with at least 32 digits? Thank you.
POSTED BY: Nicolas Legnazzi
5 Replies
Sort By:

Maybe:

  f[k_, r_] := LaguerreL[SetPrecision[k, 100], 2, SetPrecision[r, 100]]
  f[3.33, 10.14]

  (*-16.253378012832750669487606211204418150244508376350192594107493361445\
  8686734122774716077406778543804*)
POSTED BY: Mariusz Iwaniuk

Since your arguments only have machine precision the output will be limited to machine precision. If you input the arguments with more precision this will then be automatically be used throughout the calculation:

Gamma[3.33`100, 10.14`100]
POSTED BY: Sander Huisman

Brilliant! Many thanks. You have solved my problem, now I will be able to continue investigating. Thank you again.
POSTED BY: Nicolas Legnazzi

Hi, I have a new question. How can I make Mathematica interpret that the variable of a function must be worked with the precision that I want. For example, I would like Mathematica to understand that the argument of my Laguerre polynomial is written with 100 significant figures, but I cannot do this: 

LaguerreL[k, 2, r´100]

As in the future I am going to incorporate the Laguerre polynomials into an integral, I need precision to be incorporated into the function. Thank you

POSTED BY: Nicolas Legnazzi

Thanks! You solved my problem!
POSTED BY: Nicolas Legnazzi
Reply to this discussion
Community posts can be styled and formatted using the Markdown syntax.
Tag limit exceeded
Note: Only the first five people you tag will receive an email notification; the other tagged names will appear as links to their profiles.
Reply Preview
Attachments
Remove
or Discard

Group Abstract Group Abstract