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## RE: How do script commands differ from term commands?

 From: Hall, Benjamin Subject: RE: How do script commands differ from term commands? Date: Thu, 7 Apr 2005 08:09:49 -0400

```How are you using your function "f"?  Remember, Octave is designed for
numerical computations, so you have to explicitly give numeric values to the
function.  For example:

octave:1> function y = f(x)
> y = cos(x/2)+x;
> end

octave:2> f(3)
ans = 3.0707

octave:4> x = [37 33 20 19];
octave:5> f(x)
ans =

37.940  32.298  19.161  18.003

But trying to run the function by itself doesn't work:

octave:3> f
error: `x' undefined near line 2 column 9
error: evaluating binary operator `/' near line 2, column 10
error: evaluating argument list element number 1
error: evaluating binary operator `+' near line 2, column 13
error: evaluating assignment expression near line 2, column 3
error: called from `f'
octave:3>

Does that help?

-----Original Message-----
From: Peder Møller [mailto:address@hidden
Sent: Wednesday, April 06, 2005 7:40 AM
To: octave help mailing list
Subject: Re: How do script commands differ from term commands?

Hmm...

I figure it is not a command problem, but rather an installation
problem since a simple file with the commands below does not work
either.

function y = f (x)
y = cos(x/2)+x;
end

Any ideas what the problem might be? The error message is:

error: `x' undefined near line 2 column 9
error: evaluating binary operator `/' near line 2, column 10
error: evaluating argument list element number 1
error: evaluating binary operator `+' near line 2, column 13
error: evaluating assignment expression near line 2, column 3
error: called from `f' in file `/octave_files/f.m'

Sorry for spamming in this way...

- Peder

On Apr 6, 2005 12:52 PM, Peder Møller <address@hidden> wrote:
> Hi,
>
> How do script commands differ from term commands?
>
> The lines below work fine if typed into the command term of Octave,
> however, they do NOT work if typed as they are into a .m file. What
> should I change?
>
> - Peder
>
> function xdot = f (x, t)
>
> r = 0.25;
> k = 1.4;
> a = 1.5;
> b = 0.16;
> c = 0.9;
> d = 0.8;
>
> xdot(1) = r*x(1)*(1 - x(1)/k) - a*x(1)*x(2)/(1 + b*x(1));
> xdot(2) = c*a*x(1)*x(2)/(1 + b*x(1)) - d*x(2);
>
> endfunction
>
> x0 = [1; 2];
>
> t = linspace (0, 50, 200)';
>
> x = lsode ("f", x0, t);
>
> plot (t, x)
>
>
> --
> Something unknown is doing we don't know what;
>
> Sir Arthur Eddington (1882 - 1944)
>

--
Something unknown is doing we don't know what;

Sir Arthur Eddington (1882 - 1944)

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