Solver and the GAMMA function

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mcc
Posts: 157
Joined: Fri Jun 23, 2017 3:10 am

Solver and the GAMMA function

Post by mcc » Tue Apr 10, 2018 3:41 pm

Hi,

is this a glitch in the Matrix?

LBL "f"
MVAR "x"
RCL "x"
GAMMA
10
-
.END.

After calling "f" via the solver I did
0
"x"
10
"x"
"x"

and got 4.39007765083....

then
EXIT
EXIT
to go back to the "desktop" :) and CLST

then same procedure as last year, Miss Sophie and

0
"x"
100
"x"
"x"

...results in 50.

?

Gamma is (WARNING! DENGLISH ahead) steadily growing...but two roots?
Calling f with 50 manually result in 6.something.

Any hint what I did wrong?

Cheers!
Meino
DM 42 - SN: 00373, Firmware v.:3.7 / 3.7.1 as compiled by SwissMicros

Thomas Okken
Posts: 455
Joined: Tue May 02, 2017 3:48 pm
Contact:

Re: Solver and the GAMMA function

Post by Thomas Okken » Tue Apr 10, 2018 7:26 pm

Clearly SOLVE isn't handling this as well as it should, but 0 is a terrible starting guess for GAMMA. Try 1 instead. :D

Thomas Okken
Posts: 455
Joined: Tue May 02, 2017 3:48 pm
Contact:

Re: Solver and the GAMMA function

Post by Thomas Okken » Wed Apr 11, 2018 7:37 pm

mcc wrote:
Tue Apr 10, 2018 3:41 pm
Calling f with 50 manually result in 6.something.
When you say "calling f with 50 manually," do you mean

50 XEQ "f"

? Because that doesn't work; you must do

50 STO "x" XEQ "f"

since the function gets its parameter from the variable "x", not from the stack.

(In case your 6.something meant 6.somethingE62, ignore this whole post.)

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