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## Re: integral; changed to quad example

 From: Marek Szczypinski Subject: Re: integral; changed to quad example Date: Sat, 20 Aug 2005 11:16:59 +0200 (CEST)

My guess is that You are using function which operates on vectors and in the manual:
```(about function one want to integrate)... It must have the form

y = f (x)

where y and x are scalars

```
Maybe it is the problem. The ABNORMAL RETURN FROM DQAGP seems to be a message from inside of the fortran subroutine DQAGP which is used by quad.
```Hope this helps.
Marek

Homo sum, humani nihil a me alienum puto.

On Fri, 19 Aug 2005, Henry F. Mollet wrote:

```
```GNU Octave, version 2.1.71 (powerpc-apple-darwin8.1.0).
Example for using quad is given below. Results as given in the example but
what is ABNORMAL RETURN FROM DQAGP?
Henry

octave:10> function y = f (x)
```
```y = x .* sin (1 ./ x) .* sqrt (abs (1 - x));
endfunction
```
```octave:11> [v, ier, nfun, err] = quad ("f", 0, 3)
ABNORMAL RETURN FROM DQAGP
v = 1.9819
ier = 1
nfun = 5061
err =  1.1522e-07

on 8/19/05 2:01 AM, Marek Szczypinski at address@hidden wrote:

```
```Hi,
Try:
http://www.octave.org/doc/Functions-of-One-Variable.html
maybe this will help
Marek

Homo sum, humani nihil a me alienum puto.

On Thu, 18 Aug 2005, Fred J. wrote:

```
```Hello

I need to do an integration

integrate_0^(x-1/2) integrate_(1/2+y)^0 12xy(1-y) dx
dy

how can I use octave to do this. I have been reading a
lot in the
first few pages of the manual but need to know if this
is even do-able
with octave?

thanks

____________________________________________________
http://www.yahoo.com/r/hs

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```

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```

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```

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Octave is freely available under the terms of the GNU GPL.

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Subscription information:  http://www.octave.org/archive.html
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```