# Plotting level curves

First set up the complex valued function to plot.

```
% f = @(z) z.^2;
f = @(z) cosh(z);
```

Next setup the grid to evaluate the function.

x = linspace(-2,2,401); y = linspace(-2,2,401); [xx,yy] = meshgrid(x,y);

Evaluate the function and get the real and imaginary parts.

ff = f(xx+1i*yy); uu = real(ff); vv = imag(ff);

Plot the results.

contour(xx,yy,uu,25,'r'); hold on; contour(xx,yy,vv,25,'b'); hold off; axis square; xlabel('Re(z)'); ylabel('Im(z)');