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How to determine CPU and memory consumption from inside a process?
... now;
lastUserCPU = user;
lastSysCPU = sys;
return percent * 100;
}
Linux
On Linux the choice that seemed obvious at first was to use the POSIX APIs like getrusage() etc. I spent some time trying to get this to work, but never got meaningful values. When I finally checked the kern...
Bitwise operation and usage
...bit at a time.
AND is 1 only if both of its inputs are 1, otherwise it's 0.
OR is 1 if one or both of its inputs are 1, otherwise it's 0.
XOR is 1 only if exactly one of its inputs are 1, otherwise it's 0.
NOT is 1 only if its input is 0, otherwise it's 0.
These can often be best shown as truth ...
How to compute the similarity between two text documents?
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10 Answers
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Efficient way to determine number of digits in an integer
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107
Well, the most efficient way, presuming you know the size of the integer, would be a lookup. S...
How to use hex color values
...f, green ff and blue ff. You can write hexadecimal notation in Swift using 0x prefix, e.g 0xFF
To simplify the conversion, let's create an initializer that takes integer (0 - 255) values:
extension UIColor {
convenience init(red: Int, green: Int, blue: Int) {
assert(red >= 0 &&...
Auto-center map with multiple markers in Google Maps API v3
...tLngBounds();
var infowindow = new google.maps.InfoWindow();
for (i = 0; i < locations.length; i++) {
var marker = new google.maps.Marker({
position: new google.maps.LatLng(locations[i][1], locations[i][2]),
map: map
});
//extend the bounds to include each marker's position
...
Grep characters before and after match?
... characters after
$> echo "some123_string_and_another" | grep -o -P '.{0,3}string.{0,4}'
23_string_and
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Is there an equivalent of 'which' on the Windows command line?
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Windows Server 2003 and later (i.e. anything after Windows XP 32 bit) provide the where.exe program which does some of what which does, though it matches all types of files, not just executable commands. (It does not match built-in shell co...
Combine two columns of text in pandas dataframe
I have a 20 x 4000 dataframe in Python using pandas. Two of these columns are named Year and quarter . I'd like to create a variable called period that makes Year = 2000 and quarter= q2 into 2000q2 .
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Multiple aggregations of the same column using pandas GroupBy.agg()
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You can simply pass the functions as a list:
In [20]: df.groupby("dummy").agg({"returns": [np.mean, np.sum]})
Out[20]:
mean sum
dummy
1 0.036901 0.369012
or as a dictionary:
In [21]: df.groupby('dummy').agg({'returns':
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