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How do I get the row count of a pandas DataFrame?
...setup=lambda n: pd.DataFrame(np.arange(n * 3).reshape(n, 3)),
n_range=[2**k for k in range(25)],
kernels=[
lambda data: data.shape[0],
lambda data: data[0].count(),
lambda data: len(data.index),
],
labels=["data.shape[0]", "data[0].count()", "len(data.index)"]...
Javascript shorthand ternary operator
...g for, where it defaults if undefined?
var foo = bar || 1; // 1
var bar = 2;
foo = bar || 1; // 2
By the way, this works for a lot of scenarios, including objects:
var foo = bar || {}; // secure an object is assigned when bar is absent
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Correct way of using JQuery-Mobile/Phonegap together?
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edited Oct 22 '15 at 19:36
user241244
answered Oct 10 '12 at 13:59
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How to convert Java String into byte[]?
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edited Mar 31 '16 at 21:54
answered Sep 2 '13 at 10:46
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Disable a group of tests in rspec?
... in the output:
before { skip("Awaiting a fix in the gem") }
with RSpec 2:
before { pending }
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Join a list of items with different types as string in Python
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answered Aug 28 '10 at 9:09
Mark ByersMark Byers
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How do I immediately execute an anonymous function in PHP?
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121
For PHP7: see Yasuo Ohgaki's answer: (function() {echo 'Hi';})();
For previous versions: the o...
Can you have if-then-else logic in SQL? [duplicate]
...e1 WHERE project = 1
ELSE IF ((SELECT COUNT(*) FROM table1 WHERE project = 2) > 0)
SELECT product, price FROM table1 WHERE project = 2
ELSE IF ((SELECT COUNT(*) FROM table1 WHERE project = 3) > 0)
SELECT product, price FROM table1 WHERE project = 3
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Why should hash functions use a prime number modulus?
...ong time ago, I bought a data structures book off the bargain table for $1.25. In it, the explanation for a hashing function said that it should ultimately mod by a prime number because of "the nature of math".
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