how to clear the warning negative data ignored?

clc; clear all; close all; w=18; p=103; n=2; q21=0.07; q20=0.91; q22=0.0071; fid=fopen('proj12.dat','w'); for ks=65:10:100 ks pe=0; for k=0:1:w-1 c=((factorial(w-k))/factorial(w))*(factorial(w-1)/factorial(w-k-1)); for y=0:1:w-2 z=((factorial(w-y))/factorial(w))*(factorial(w-2)/factorial(w-y-2)) d=q20+(c*(q21))+(z*(q22)); e=(d^((ks)-1)); for j=0:1:w pe1=(factorial(w)/((factorial(w-j))*factorial(j))); x=pe1*e; pe2=((-1)^j)*x; pe=pe+pe2; end end

        end
        pez=pe/2
 fprintf(fid,'%2d %5.3e \n',ks,pez);

end

fclose(fid);

while plottig the graph for above program i had a warning that negative data ignored....how to clear it?

Answer 1

[Matt Tearle]

Use lastwarn to find the identifier of the warning message, then use warning to turn it off. Once you know the identifier, you can put the warning command at the beginning of your script.

Example:

x = linspace(-1,1);
semilogy(x,x.^3)
%  I get a warning message
[~,foo] = lastwarn
%  Now I know the identifier: 'MATLAB:Axes:NegativeDataInLogAxis'
warning('off','MATLAB:Axes:NegativeDataInLogAxis')
semilogy(x,x.^5)

Answer 2

[Walter Roberson]

Better yet, plot max(0,x) to force there to be no negative data. (The 0's will be a problem on the log plot, though...)