[Matplotlib-users] How to convert time to angle in matplotlib's spectrogram?

I have a pressure transducer signal along with the crank angle from an internal combustion engine. A sample data is available here . Now, I am trying to plot the spectrogram of this pressure signal using the code below

[Matplotlib-users] How to create ternary contour plot in matplotlib?

I am trying to create ternary plots with matplotlib as shown in the figure ( source ). The axes are A, B, C and D values should be denoted by contours and the points need to be labelled like in figure. [image: enter image