An Introduction to Python For Undergraduate Engineers/While Loops

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While loops will repeat a section of code whilst a logical test is true.

Instead of repeating something with a defined list of values or a set number of times, a while loop will happily continue repeating its section of code until a logical test is satisfied. For example

   done = False             # Creates a variable and gives it the logical vlue 'False'
   count = 0                # Creates a variable and gives it integer value 0
   while done == False:     # Repeats following code until logical test no longer satisfied
       count = count + 1    # Adds 1 to value of count variable
       print("The value of count is... " + str(count))   # Prints value of count

The same code could also be written using != which means NOT EQUAL TO, for example:

   done = False             
   count = 0                
   while done != True:     
       count = count + 1    
       print("The value of count is... " + str(count))