The dashed lines indicate singularities, and I find them helpful.
They can’t be removed, however it is possible to get the XData and YData from fplot and re-plot them.
syms x
y = 1/(x^2-2*x-1);
figure
hfp = fplot(y, [-5 5]);
X = hfp.XData;
Y = hfp.YData;
Y(Y>100) = NaN;
figure
plot(X, Y)
grid
ylim(hfp.Parent.YLim)
That’s the only way I’ve found not to plot the singularity llines.
Make appropriate changes to get the result you want.
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