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Iterating over a numpy array
...>>> for (x,y), value in numpy.ndenumerate(a):
... print x,y
...
0 0
0 1
1 0
1 1
2 0
2 1
Regarding the performance. It is a bit slower than a list comprehension.
X = np.zeros((100, 100, 100))
%timeit list([((i,j,k), X[i,j,k]) for i in range(X.shape[0]) for j in range(X.shape[1]) for k...
Gem::LoadError for mysql2 gem, but it's already in Gemfile
... with rails 4.1.5) try using this version of mysql2:
gem 'mysql2', '~> 0.3.18'
Apparently mysql2 isn't still compatible with newer version of rails because rails 4.2.4 is pretty new as the time of answering this question by me 8 September 2015 so use the above line in your Gem file and run:
...
How to round a number to n decimal places in Java
...ngMode(RoundingMode.CEILING);
for (Number n : Arrays.asList(12, 123.12345, 0.23, 0.1, 2341234.212431324)) {
Double d = n.doubleValue();
System.out.println(df.format(d));
}
gives the output:
12
123.1235
0.23
0.1
2341234.2125
EDIT: The original answer does not address the accuracy of th...
Is there a splice method for strings?
...
10 Answers
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Fast stable sorting algorithm implementation in javascript
I'm looking to sort an array of about 200-300 objects, sorting on a specific key and a given order (asc/desc). The order of results must be consistent and stable.
...
What does value & 0xff do in Java?
... = value;
then result would end up with the value ff ff ff fe instead of 00 00 00 fe. A further subtlety is that the & is defined to operate only on int values1, so what happens is:
value is promoted to an int (ff ff ff fe).
0xff is an int literal (00 00 00 ff).
The & is applied to yield...
What does ~~ (“double tilde”) do in Javascript?
...result is a number.
In other words, it yields:
function(x) {
if(x < 0) return Math.ceil(x);
else return Math.floor(x);
}
only if x is between -(231) and 231 - 1. Otherwise, overflow will occur and the number will "wrap around".
This may be considered useful to convert a function's string...
Append a NumPy array to a NumPy array
...
answered Mar 19 '12 at 18:01
endolithendolith
19.6k2424 gold badges107107 silver badges170170 bronze badges
...
Manifest merger failed : uses-sdk:minSdkVersion 14
...o not use dynamic updating.
compile 'com.android.support:support-v4:21.0.0'
}
fixed the issue.
Make sure you're not doing a general inclusion of com.android.support:support-v4:+ or any other support libraries (v7, v13, appcompat, etc), anywhere in your project.
I'd assume the problem is v4...
Checking if a string can be converted to float in Python
...
Richard Simões
10.6k44 gold badges3737 silver badges4949 bronze badges
answered Apr 9 '09 at 21:55
dbrdbr
...