Prandtl Meyer Expansion fan solver function

A function made to solve supersonic Prandtl Meyer expansion fan with different input cases

This function solves Prandtl Meyer expansion using the relations given in "Modern Compressible Flow With Historical Prespective-John D. Anderson Jr"

• It is only accurate in the range for mach number M=[1,7] because I used an approximate relation in one of the cases
• You can solve for different cases depending on the given data for your problem, the values assigned for the flags determine the case you want to solve for.
• variables names ending with 3 refer to the stream before expansion.
• variables names ending with 4 refer to the stream after expansion.
• I used 3 and 4 for consistency with an oblique shock function I created before this.