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How to iterate through two lists in parallel?
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edited Jun 9 '19 at 20:46
Tobias Kolb
9461111 silver badges2626 bronze badges
answered Nov 2 '09 at...
iOS White to Transparent Gradient Layer is Gray
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clearColor has a black color channel with an alpha of 0, so I had to use
[UIColor colorWithWhite:1 alpha:0]
and it works fine.
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How to round a number to significant figures in Python
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20 Answers
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Constructor overload in TypeScript
...tor overloading in TypeScript. On page 64 of the language specification (v 0.8), there are statements describing constructor overloads, but there wasn't any sample code given.
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Seeding the random number generator in Javascript
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edited May 23 '17 at 12:02
Community♦
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answered Feb 6 '09 at 17:42
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pytest: assert almost equal
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I noticed that this question specifically asked about py.test. py.test 3.0 includes an approx() function (well, really class) that is very useful for this purpose.
import pytest
assert 2.2 == pytest.approx(2.3)
# fails, default is ± 2.3e-06
assert 2.2 == pytest.approx(2.3, 0.1)
# passes
# also...
Can dplyr package be used for conditional mutating?
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220
Use ifelse
df %>%
mutate(g = ifelse(a == 2 | a == 5 | a == 7 | (a == 1 & b == 4), 2,
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How do I cast a string to integer and have 0 in case of error in the cast with PostgreSQL?
...hould work:
SELECT CASE WHEN myfield~E'^\\d+$' THEN myfield::integer ELSE 0 END FROM mytable;
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Using bitwise OR 0 to floor a number
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Odd Comparative behavior: Math.floor(NaN) === NaN, while (NaN | 0) === 0
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Ruby, remove last N characters from a string?
..._suffix!('123') # => "abc"
It's even significantly faster (almost 40% with the bang method) than the top answer. Here's the result of the same benchmark:
user system total real
chomp 0.949823 0.001025 0.950848 ( 0.951941)
range ...