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Comparing two NumPy arrays for equality, element-wise
...rt numpy as np H = 1/np.sqrt(2)*np.array([[1, 1], [1, -1]]) #hadamard matrix np.array_equal(H.dot(H.T.conj()), np.eye(len(H))) # checking if H is an unitary matrix or not H is an unitary matrix, so H x H.T.conj is an identity matrix. But np.array_equal returns False
– Dex
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How to convert a PIL Image into a numpy array?
...PIL image object back and forth to a numpy array so I can do some faster pixel by pixel transformations than PIL's PixelAccess object would allow. I've figured out how to place the pixel information in a useful 3D numpy array by way of:
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Create a tar.xz in one command
I am trying to create a .tar.xz compressed archive in one command. What is the specific syntax for that?
5 Answers
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How to get execution time in rails console?
I want compare time of execution Post.all and SELECT * FROM posts (or some other statements) How can i get execution time of Post.all ?
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What is the equivalent of the C# 'var' keyword in Java?
...yword in C# is implicit type declaration. What is the Java equivalent syntax for var ?
15 Answers
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Android get color as string value
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This is not working any more, error 'Expected resource of type String'
– Clive Jefferies
Mar 5 '15 at 15:29
21
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Using unset vs. setting a variable to empty
...ides returning a return code, set some meaningful message saying what was expected.
4 Answers
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ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: YES)
...most cases you should also set up individual user accounts before working extensively with the DB as well.
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How do I check for null values in JavaScript?
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Javascript is very flexible with regards to checking for "null" values. I'm guessing you're actually looking for empty strings, in which case this simpler code will work:
if(!pass || !cpass || !email || !cemail || !user){
Which will check for ...
Retina displays, high-res background images
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Do I need to double the size of the .box div to 400px by 400px to
match the new high res background image
No, but you do need to set the background-size property to match the original dimensions:
@media (-webkit-min-device-pixel-ratio: 2),
(min-resolution: 1...