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What's the point of g++ -Wreorder?
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260
Consider:
struct A {
int i;
int j;
A() : j(0), i(j) { }
};
Now i is initialized t...
In Python, how do I convert all of the items in a list to floats?
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470
[float(i) for i in lst]
to be precise, it creates a new list with float values. Unlike the map...
How to check if smtp is working from commandline (Linux) [closed]
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edited Aug 15 '19 at 16:20
rogerdpack
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ans...
Ternary operator is twice as slow as an if-else block?
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10 Answers
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How to add image to canvas
....png';
base_image.onload = function(){
context.drawImage(base_image, 0, 0);
}
}
I.e. draw the image in the onload callback of the image.
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How do I interpret precision and scale of a number in a database?
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406
Numeric precision refers to the maximum number of digits that are present in the number.
ie 1...
Select by partial string from a pandas DataFrame
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Based on github issue #620, it looks like you'll soon be able to do the following:
df[df['A'].str.contains("hello")]
Update: vectorized string methods (i.e., Series.str) are available in pandas 0.8.1 and up.
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Format decimal for percentage values?
...se the P format string. This will vary by culture:
String.Format("Value: {0:P2}.", 0.8526) // formats as 85.26 % (varies by culture)
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Selecting with complex criteria from pandas.DataFrame
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406
Sure! Setup:
>>> import pandas as pd
>>> from random import randint
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Difference between var_dump,var_export & print_r
...the result.
// var_dump(array('', false, 42, array('42')));
array(4) {
[0]=> string(0) ""
[1]=> bool(false)
[2]=> int(42)
[3]=> array(1) {[0]=>string(2) "42")}
}
print_r is for debugging purposes, too, but does not include the member's type. It's a good idea to use if you k...