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Find the max of two or more columns with pandas
...df = pd.DataFrame({"A": [1,2,3], "B": [-2, 8, 1]})
>>> df
A B
0 1 -2
1 2 8
2 3 1
>>> df[["A", "B"]]
A B
0 1 -2
1 2 8
2 3 1
>>> df[["A", "B"]].max(axis=1)
0 1
1 8
2 3
and so:
>>> df["C"] = df[["A", "B"]].max(axis=1)
>>> df
...
How to count the number of true elements in a NumPy bool array
...xample:
>>> import numpy as np
>>> boolarr = np.array([[0, 0, 1], [1, 0, 1], [1, 0, 1]], dtype=np.bool)
>>> boolarr
array([[False, False, True],
[ True, False, True],
[ True, False, True]], dtype=bool)
>>> np.sum(boolarr)
5
Of course, that is ...
iOS UIImagePickerController result image orientation after upload
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Why is January month 0 in Java Calendar?
In java.util.Calendar , January is defined as month 0, not month 1. Is there any specific reason to that ?
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Interpolating a string into a regex
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answered Sep 29 '08 at 18:53
Jonathan LonowskiJonathan Lonowski
108k3131 gold badges188188 silver badges191191 bronze badges
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Matplotlib different size subplots
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390
Another way is to use the subplots function and pass the width ratio with gridspec_kw:
import n...
Why does parseInt(1/0, 19) return 18?
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The result of 1/0 is Infinity.
parseInt treats its first argument as a string which means first of all Infinity.toString() is called, producing the string "Infinity". So it works the same as if you asked it to convert "Infinity" in base 19 ...
Optional Parameters with C++ Macros
...rd trick to count the number of arguments to a macro.
enum
{
plain = 0,
bold = 1,
italic = 2
};
void PrintString(const char* message, int size, int style)
{
}
#define PRINT_STRING_1_ARGS(message) PrintString(message, 0, 0)
#define PRINT_STRING_2_ARGS(message, size) ...
Does .NET provide an easy way convert bytes to KB, MB, GB, etc.?
...izeSuffix(Int64 value, int decimalPlaces = 1)
{
if (decimalPlaces < 0) { throw new ArgumentOutOfRangeException("decimalPlaces"); }
if (value < 0) { return "-" + SizeSuffix(-value); }
if (value == 0) { return string.Format("{0:n" + decimalPlaces + "} bytes", 0); }
// mag is 0 ...
Determine font color based on background color
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