Professional IronPython

lISTINg 4-5: 
 Accessing specific array elements
# Create the array.
continues
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62
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CHAPTER 4
Using ArrAys And ColleCtions
MyList = [1, 2, 3, 4, 5, 6]
# Access every other element.
for Output in MyList[::2]:
print Output
FIguRE 4-4: 
You can use complex expressions to create arrays.
The output is 1, 3, and 5 for this example. Actually, you can provide more than the step for the 
output. IronPython provides the means to provide start:stop:step with the colons. For example, if 
you wanted to start with element 1 instead of element 0, you’d type:
for Output in MyList[1::2]:
print Output
This code outputs 2, 4, and 6 based on the previous input. You can control things even more. For 
example, look at the following code.
for Output in MyList[1:4:2]:
print Output
Run this code and you’ll see 2 and 4 as output. The code begins with element 1, stops with element 4, 
and uses a step of 2.
Let’s look at one other interesting IronPython array technique. Listing 4-6 shows code that not only 
shows the array items, but also the index associated with that item.
lISTINg 4-6: 
 Looping through array elements
# Create the array.
MyList = [‘Zero’, ‘One’, ‘Two’, ‘Three’, ‘Four’]
# Display the items and their index.
for index, item in enumerate(MyList):
print index, item
# Pause after the debug session.
raw_input(‘Press any key to continue...’)
lISTINg 4-5 
(continued)
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Working with Tuples, Lists, and Arrays