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How to add a new row to an empty numpy array
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The way to "start" the array that you want is:
arr = np.empty((0,3), int)
Which is an empty array but it has the proper dimensionality.
>>> arr
array([], shape=(0, 3), dtype=int64)
Then be sure to append along axis 0:
arr = np.append(arr, np.array([[1,2,3]]), axis=0)
arr =...
Delete the first three rows of a dataframe in pandas
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edited Oct 17 '18 at 1:06
Acumenus
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Why does ('0' ? 'a' : 'b') behave different than ('0' == true ? 'a' : 'b') [duplicate]
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208
+500
First, ...
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...
Lost connection to MySQL server at 'reading initial communication packet', system error: 0
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107
Someone here suggests that it might be a firewall problem:
I have just had this problem and...
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
10
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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...
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
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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 &&...