how to get an isodensity plot

how can i get an isodensity plot from an image? the first image is the one I am given. the other two is how i want it to look like.

Answer 1

[Chunru]

[x,y,z] = peaks(25);    % Use your data
contourf(x,y,z)

[Naomi Penelope]

how can i call the txt file into the contourf?

[Chunru]

Read the document of importing data. 'doc textscan' for info.