Pygame 7

 Worked through Pygame 7 on Codemy. The issue: getting

the hero in the game to stay within the screen space. Clearly, need 

to add a condition on movement with the keys. For the right

edge and the bottom, should subtract the image dimension as well...

                                                        

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I was asked to explain the polar form of complex numbers. 

I mentionned yesterday that, on the complex plane, both dimensions are needed

just to define a single point. Thus making computation more difficult. Polar 

form simplifies things in that one identifies our value with a radius length and an angle.

                                                    

                                        

One still does addition with rectangular form:

                                         

But multiplication becomes simple:

                                                                             

Changes in angle dimensions can be handled by de Moivre's formula:

There are problem sets available on line....