Often we won’t be iterating through a specific list (or any collection), but rather only want to perform a certain action multiple times.
For example, if we wanted to print out a "Learning Loops!"
message six times using a for
loop, we would follow this structure:
for <temporary variable> in <list of length 6>:
print("Learning Loops!")
Notice that we need to iterate through a list with a length of six, but we don’t necessarily care what is inside of the list.
To create arbitrary collections of any length, we can pair our for
loops with the trusty Python built-in function range()
.
An example of how the range()
function works, this code generates a collection of 6 integer elements from 0
to 5
:
six_steps = range(6) # six_steps is now a collection with 6 elements: # 0, 1, 2, 3, 4, 5
We can then use the range directly in our for
loops as the collection to perform a six-step iteration:
for temp in range(6): print("Learning Loops!")
Would output:
Learning Loops! Learning Loops! Learning Loops! Learning Loops! Learning Loops! Learning Loops!
Something to note is we are not using temp
anywhere inside of the loop body. If we are curious about which loop iteration (step) we are on, we can use temp
to track it. Since our range starts at 0
, we will add + 1
to our temp
to represent how many iterations (steps) our loop takes more accurately.
for temp in range(6): print("Loop is on iteration number " + str(temp + 1))
Would output:
Loop is on iteration number 1 Loop is on iteration number 2 Loop is on iteration number 3 Loop is on iteration number 4 Loop is on iteration number 5 Loop is on iteration number 6
Let’s try out using a range in a for
loop!
Instructions
Use the range()
function in a for
loop to print()
out the provided promise
variable five times.