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From: "David Doria" <daviddoria@gmail.com>
Newsgroups: comp.soft-sys.matlab
Subject: blank ezplot?
Date: Fri, 30 Oct 2009 16:10:19 +0000 (UTC)
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If I have this function:
function PlotPolynomialClassifier(W)
syms x;
syms y;
f = W(1) + W(2) * x + W(3) * y + W(4) * x^2 + W(5) * y^2; %doesn't work
%f = W(1) + W(2) * x + W(3) * y + W(4) * x^2; %works
ezplot(f);

When I call it with this vector:
a=[62 -1.8 38 .01 18];

it produces an empty plot. I used solve(f,y) =  ((648*x)/5 - (18*x^2)/25 - 3020)^(1/2)/36 - 19/1 to see if there are any problems with the function (divide by zero or something like that) but it doesn't look like it.

Does anyone know why this would be producing an empty plot?

Thanks,

Dave