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Python: Find in list
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As for your first question: that code is perfectly fine and should work if item equals one of the elements inside myList. Maybe you try to find a string that does not exactly match one of the items or maybe you are using a float value which suffers from inaccuracy.
As for your se...
Double Iteration in List Comprehension
...y don't have much meaning to me! Suppose you have a text full of sentences and you want an array of words.
# Without list comprehension
list_of_words = []
for sentence in text:
for word in sentence:
list_of_words.append(word)
return list_of_words
I like to think of list comprehension a...
Pythonic way to combine FOR loop and IF statement
I know how to use both for loops and if statements on separate lines, such as:
10 Answers
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Is git's semi-secret empty tree object reliable, and why is there not a symbolic name for it?
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So I guess it is safer to define a variable with the result of that command as your empty sha1 tree (instead of relying of a "well known value").
Note: Git 2.25.1 (Feb. 2020) proposes in commit 9c8a294:
empty_tree=$(git mktree </dev/null)
# Windows:
git mktree <NUL
And adds:
As a hi...
range() for floats
...mp):
while x < y:
yield float(x)
x += decimal.Decimal(jump)
And then:
>>> list(drange(0, 100, '0.1'))[-1]
99.9
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Resetting generator object in Python
...ls.tee) - this uses lazy load strategy, so items to list copied only on demand
– Dewfy
Aug 13 '09 at 13:23
11
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What is the best regular expression to check if a string is a valid URL?
...$IRI . '|' . $irelative_ref);
Edit 7 March 2011: Because of the way PHP handles backslashes in quoted strings, these are unusable by default. You'll need to double-escape backslashes except where the backslash has a special meaning in regex. You can do that this way:
$escape_backslash = '/(?<!...
ReactJS: Modeling Bi-Directional Infinite Scrolling
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This is a mix of an infinite table and an infinite scroll scenario. The best abstraction I found for this is the following:
Overview
Make a <List> component that takes an array of all children. Since we do not render them, it's really cheap to just all...
Reading from text file until EOF repeats last line [duplicate]
...ion. x is still 30 from previous iteration. Now you read from the stream and you get EOF. x remains 30 and the ios::eofbit is raised. You output to stderr x (which is 30, just like in the previous iteration). Next you check for EOF in the loop condition, and this time you're out of the loop.
T...
List comprehension in Ruby
... % 2 == 0 ? x * 3 : nil}.compact
Slightly cleaner, at least to my taste, and according to a quick benchmark test about 15% faster than your version...
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