I've often needed to take out or reorder the columns in a list of lists. I'm embarrased to say it took me a while to think of this, it's so simple, but I looked around and have not found any examples of it, so...
Python, 12 lines
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Copy to clipboard1 2 3 4 5 6 7 8 9 10 11 12 | # 1, 2, 3
# 4, 5, 6
# 7, 8, 9
#Task: remove the middle column
temp = [[1,2,3],[4,5,6],[7,8,9]]
newTemp = [[x[0],x[2]] for x in temp]
#now newTemp is:
# 1, 3
# 4, 6
# 7, 9
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I can't think why I've never seen this before; it strikes me as it belongs in the intro of list comprehensions. I looked through several books, and never saw anything refering to subscripting and list comprehensions. Perhaps I'm slow, or perhaps this is just one of those blind spots.
