Use the Matrix Histogram plot in 2D () when you have a precomputed matrix that you want to visualize as a 2D histogram. In a fatigue analysis use it to display the stress cycle distribution of the rainflow counting, for example. It shows the number of cycles with a certain stress amplitude and a certain mean stress in the load history. You can also use this plot to visualize how the damage is distributed between the different stress levels. If a large fraction of the total damage is caused by loads that occur only a few times, the statistical sample of the loads may be too small to reach any good conclusions.