I have a problem with semilogx command
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Hello,
I want to have the x axis as a log scale however it doesn't want to work. This function basically plots cubic splines in order to generate a p-v diagram, however when i run the code it only gets the splines that are shaded onwards, so the first half of the graph is missing.
Any help?
Thank you
function pv_plot(V,c1,c2,c3, c4, V_input_1, V_input_2)
for i = 2:72
x = V(i-1):((V(i+1)- V(i))/100):V(i);
y = (c1(i).*((V(i+1)-x).^3))+(c2(i).*((x-V(i)).^3))+(c3(i).*(V(i+1)-x))+(c4(i).*(x-V(i)));
semilogx(x,y)
if V(i-1)>V_input_1 && V(i)<V_input_2
H = area (x,y, 'EdgeColor', 'r');
hold on;
set(H(1), 'FaceColor', 'r');
end
end
hold off
end
4 个评论
Walter Roberson
2019-12-9
Your plot has broken lines that hint you have infinity or nan values in your inputs.
dpb
2019-12-9
Let's see enough to reproduce the actual data. What was the input to the function or attach x,y as .mat file.
semilogx won't handle negative values if something goes wrong for x...that we can't see.
Walter's comment is apropos, too, fer shure...
Nadine Nassar
2019-12-10
Walter Roberson
2019-12-10
Copies of V,c1,c2,c3, c4, V_input_1, V_input_2 would allow us to test the code to track down the problem.
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2019-12-9
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