Gamma function question

[roadrunner]

Hello Everybody,

When I enter Gamma(0.25,0.25) on the HP Prime I get -1:
   
In xcas I get 0.929323783277:
   
Gamma(0.25,0.75) returns 0.362791168887 in both xcas and prime. Does anyone know why this is occurring and what to do get the same result in prime and xcas? This is on version 8151 emulator.

Road

[Bill_G]

In the Help Menu the Gamma function is only a function of "x", where x is real.

Bill

[parisse]

I recently made some changes in upper/lower incomplete Gamma code, trying with the latest source code, I get the same on the Prime emulator as on Xcas.

[roadrunner]

(07-13-2015 04:34 PM)Bill_G Wrote:  In the Help Menu the Gamma function is only a function of "x", where x is real.

Bill

Apparently the incomplete gamma function wasn't documented because the code was ... incomplete.

[roadrunner]

Anyway, thanks for the replies. In the mean time I can do this: