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How to print a int64_t type in C
...ttypes.h>
uint64_t t;
printf("%" PRIu64 "\n", t);
you can also use PRIx64 to print in hexadecimal.
cppreference.com has a full listing of available macros for all types including intptr_t (PRIxPTR). There are separate macros for scanf, like SCNd64.
A typical definition of PRIu16 would be "...
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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Copy/duplicate database without using mysqldump
...e the target database using MySQLAdmin or your preferred method. In this example, db2 is the target database, where the source database db1 will be copied.
Execute the following statement on a command line:
mysqldump -h [server] -u [user] -p[password] db1 | mysql -h [server] -u [user] -p[password...
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
...
JavaScript object: access variable property by name as string [duplicate]
...mns['right'];
This is equal to dot notation, var side = columns.right;, except the fact that right could also come from a variable, function return value, etc., when using bracket notation.
If you NEED a function for it, here it is:
function read_prop(obj, prop) {
return obj[prop];
}
To ...
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:
...
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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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 ?
...
Retina displays, high-res background images
...
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...
Why use Abstract Base Classes in Python?
... EAFP or type introspection to confirm that the unknown object meets this expected contract.
But there are also higher-level, semantic promises in the contract.
For example, if there is a __str__() method, it is expected to return a string representation of the object. It could delete all contents o...