From help-request at octave dot org Fri Feb 18 04:25:28 2005
Subject: using quad to integral on a circle,
From: Afsshl at aol dot com
To: help at octave dot org
Date: Fri, 18 Feb 2005 05:30:25 EST
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Dear matlab/octave user:
I like to evalute an integral on a circle
which will become
so I tried to program the following matlab/octave code, but it is proved not
work
------------------------------------------------------------------------------
----------------------------------
octave:1> function z=f2(x)
> z = x^2;
> endfunction;
octave:2> function z=f(x)
> z=9*quad( at f2, -sqrt(9-x^2), sqrt(9-x^2))-3*x;
> endfunction;
octave:3> quad( at f, -3, 3)
error: quad: invalid recursive call
error: evaluating binary operator `*' near line 2, column 10
error: evaluating binary operator `-' near line 2, column 47
error: evaluating assignment expression near line 2, column 8
error: called from `f'
error: quad: evaluation of user-supplied function failed
octave:3>
------------------------------------------------------------------------------
------------------------------
please help
eric
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Dear matlab/octave user:
I like to evalute an integral on a circle
whic=
h will become

=
FONT>
=
FONT>
=
FONT>
=
FONT>
so=
I tried to program the following matlab/octave code, but it is proved not w=
ork
--=
----------------------------------------------------------------------------=
----------------------------------
=
FONT>
=
FONT>
oc=
tave:1> function z=3Df2(x)
> &nb=
sp; z =3D x^2;
> =
endfunction;
octave:2> function z=3Df(x)
> &nb=
sp; z=3D9*quad( at f2, -sqrt(9-x^2), sqrt(9-x^2))-3*x;
>=
; endfunction;
octave:3> qua=
d( at f, -3, 3)
error: quad: invalid recursive call
error: evaluating bin=
ary operator `*' near line 2, column 10
error: evaluating binary operator=
`-' near line 2, column 47
error: evaluating assignment expression near=20=
line 2, column 8
error: called from `f'
error: quad: evaluation of use=
r-supplied function failed
octave:3>
=
FONT>
=
FONT>
-----------------------------------------------------------------------=
-------------------------------------
please help
eric
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