so I am trying to create a heatmap plot for x, y data that are shaped as following:

xs, ys, corrs = [], [], []
for x in np.linspace(0.1,5,25):
    xs.append(x)
    for y in np.linspace(0.01,x,25):
        ys.append(y)
        corr = function_to_calculte_corr()
        corrs.append(corr)

Now I would like to make a heatplot of corrs in the xs, ys plane. I have tried multiple times both with imshow and pcolormesh but do not seem to find the correct way. The problem is that the ys are differently spaced for each x value and they arrive until the corresponding x value, so I should be getting a plot where above the diagonal y=x should be blank.

Any help with it? Thanks in advance 🙂