List filling patterns

In this section we will compare different ways to fill lists. They are different in computational  efficiency and also in code readability.

List filling with the append method

A ubiquitous programming pattern is to compute elements and store them in a list:

L = []
for k in range(n):
    # call various functions here
    # that compute "result"
    L.append(result)

This approach has a number of disadvantages:

  • The number of iterations is decided in advance. If there is a break instruction, then the preceding code takes care of both generating values and deciding when to stop. This is not desirable and lacks flexibility.
  • It makes the assumption that the user wants the whole history of the computation, for all the iterations. Suppose ...

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