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--- python3:list_comprehensions [2019/05/07 14:52]
jguerin Added note about tests/storage and generators.
+++ python3:list_comprehensions [2019/05/07 16:19] (current)
jguerin Moved the multiple loop example, switched x*2 to abs(x) in list example.
@@ Line 20: / Line 20: @@
 [0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
 </code>
+===== Example Functionality =====
 ==== Multiple Loops ====
-Note that this basic syntax is easily extended to multiple loops and variables:
 <code python>
 >>> [(x**2, y**2) for x in range(3) for y in range(3)]
@@ Line 28: / Line 31: @@
 </code>
-===== Examples =====
+====Conditionals====
-Conditionals:
 <code python>
 >>> [(x, y) for x in [1,2,3] for y in [3,1,4] if x != y]
@@ Line 35: / Line 37: @@
 </code>
-Repetitions:
+====Repetitions====
 <code python>
 >>> [i for i in range(1, 5) for j in range(i)]
@@ Line 41: / Line 43: @@
 </code>
-Processing non-range() iterables:
+====Processing non-range() iterables====
 <code python>
 >>> vec = [-4, -2, 0, 2, 4]
->>> [x*2 for x in vec]
+>>> [abs(x) for x in vec]
-[-8, -4, 0, 4, 8]
+[4, 2, 0, 2, 4]
+</code>
+====Creating a double list====
+<code python>
+>>> n = 3
+>>> [[i for i in range(j*n, j*n+n)] for j in range(n)]
+[[0, 1, 2], [3, 4, 5], [6, 7, 8]]
 </code>
-Flattening a double list:
+====Flattening a double list====
 <code python>
 >>> vec = [[1,2,3], [4,5,6], [7,8,9]]

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