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How to catch integer(0)?
Let's say we have a statement that produces integer(0) , e.g.
6 Answers
6
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what does -webkit-transform: translate3d(0,0,0); exactly do? Apply to body?
what does -webkit-transform: translate3d(0,0,0); exactly do?
Does it have any performance issues? Should I just apply it to the body or individual elements? It seems to improve scroll events drastically.
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How to generate random SHA1 hash to use as ID in node.js?
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edited May 23 '17 at 12:10
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answered Feb 23 '12 at 6:28
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What does (x ^ 0x1) != 0 mean?
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The XOR operation (x ^ 0x1) inverts bit 0. So the expression effectively means: if bit 0 of x is 0, or any other bit of x is 1, then the expression is true.
Conversely the expression is false if x == 1.
So the test is the same as:
if (x != 1)
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How can I obtain the element-wise logical NOT of a pandas Series?
...~s:
In [7]: s = pd.Series([True, True, False, True])
In [8]: ~s
Out[8]:
0 False
1 False
2 True
3 False
dtype: bool
Using Python2.7, NumPy 1.8.0, Pandas 0.13.1:
In [119]: s = pd.Series([True, True, False, True]*10000)
In [10]: %timeit np.invert(s)
10000 loops, best of 3: 91.8 µs...
Why are elementwise additions much faster in separate loops than in a combined loop?
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10 Answers
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How are feature_importances in RandomForestClassifier determined?
...data used on the tree?
– Cokes
Jan 20 '15 at 20:27
1
Two useful resources. (1) blog.datadive.net/...
How to drop a list of rows from Pandas dataframe?
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401
Use DataFrame.drop and pass it a Series of index labels:
In [65]: df
Out[65]:
one two...
Check substring exists in a string in C
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280
if(strstr(sent, word) != NULL) {
/* ... */
}
Note that strstr returns a pointer to the sta...
Shell equality operators (=, ==, -eq)
... guaranteed to work.
$ a=foo
$ [ "$a" = foo ]; echo "$?" # POSIX sh
0
$ [ "$a" == foo ]; echo "$?" # bash specific
0
$ [ "$a" -eq foo ]; echo "$?" # wrong
-bash: [: foo: integer expression expected
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(Side note: Quote those variable expansions! Do not leave out the double quotes ab...