error using contour z must be at least a 2x2 matrix

x = (pi/2):0.1:(2*pi);
y = (pi/2):0.1:(2*pi);
z = sin(x) + cos(y);
contour3(x,y,z)

I need a contour plot of x,y,z variables. How do i get it?

Answer 1

[Birdman]

Use meshgrid.

x = (pi/2):0.1:(2*pi);
y = (pi/2):0.1:(2*pi);
[X,Y]=meshgrid(x,y);
z = sin(X) + cos(Y);
contour3(X,Y,z)

[Aishwarya Bangalore Kumar]

Thank you sir for the help.

[Connor Fitzgerald]

@Birdman, but why meshgrid?

My code with your implementation looks like:

                plotX = app.UITablePlot.Data(:,2);
                plotY = app.UITablePlot.Data(:,3);
                plotZ = app.UITablePlot.Data(:,4);
                
                [plotX2, plotY2] = meshgrid(plotX, plotY)

                contour3(app.UIAxes, plotX2, plotY2, plotZ)

However I still receive the same error.

Answer 2

[ZEESHAN AHMED]

How to plot contour map if I have individual data for example

1. Torque (50001x1)
2. speed (50001x1)
3. efficiency(50001x13)

All of the data is taken from simulink in matrices.