comp.lang.idl-pvwave archive: archive » Re: Integration qpint

Home » Public Forums » archive » Re: Integration qpint

Show: Today's Messages :: Show Polls :: Message Navigator
E-mail to friend

Re: Integration qpint [message #81059 is a reply to message #81057]

Mon, 13 August 2012 02:01

Helder Marchetto
Messages: 520
Registered: November 2011

Senior Member

On Sunday, August 12, 2012 7:42:57 PM UTC+2, Gompie wrote:
> Hi
>
> Can anyone help. I am using qpint1d to integrate but i get
>
> "Program caused arithmetic error: Floating overflow:"
>
>
>
> The code is
>
> C1 = 1.1910427E-12
>
> c2=1.43883
>
> T=300
>
> c=c1*(c2^(-4))*T^4
>
> llimit=c2*2380/T
>
> ulimit=c2*2940/T
>
> print,"X=",llimit,ulimit
>
> lin= c*qpint1d('x^3/(EXP(X)-1)', llimit, +inf, /expr)
>
> rin=c*qpint1d('x^3/(EXP(X)-1)', ulimit, +inf, /expr)
>
> print,abs(lin-rin)
>
> end
>
>
>
> This outputs a number ( i am not sure if it is correct) but it also says floating point error.
>
> Thanks in advance
>
> Gompie

Hi Gompie,
I didn't go through the whole of your code, but you define T as an integer.
Try rerunning your code substituting this to the line where you define T:

T=300.0

Doing this, the value of c changes from 3.48598e-009 (T is integer) to 0.00225099 (T is floating point).

Maybe also change the definitions of llimit and ulimit to:
llimit=c2*2380.0/T
ulimit=c2*2940.0/T

This might help. But I have not tried the integration.

Cheers,
h

Report message to a moderator

[Message index]

		Re: Integration qpint By: Gompie on Mon, 13 August 2012 05:30
		Re: Integration qpint By: Helder Marchetto on Mon, 13 August 2012 02:01
		Re: Integration qpint By: Craig Markwardt on Mon, 13 August 2012 02:00

Previous Topic:	Integration qpint
Next Topic:	widget event structure doesn't tranfer

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

] [

]

Current Time: Wed Oct 08 19:03:46 PDT 2025

Total time taken to generate the page: 0.00384 seconds