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Static methods in Python?
...wed in other languages, but it is anyway considered a bad practice and the compiler always warns about it
– SomethingSomething
May 22 '17 at 15:40
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Summarizing multiple columns with dplyr? [duplicate]
...38 2.873786
#> 3: 3 2.854701 2.948718 2.951567 3.062678
Let's try to compare performance.
library(dplyr)
library(purrrlyr)
library(data.table)
library(bench)
set.seed(123)
n <- 10000
df <- data.frame(
a = sample(1:5, n, replace = TRUE),
b = sample(1:5, n, replace = TRUE),
c = sam...
How do I force Postgres to use a particular index?
...
Assuming you're asking about the common "index hinting" feature found in many databases, PostgreSQL doesn't provide such a feature. This was a conscious decision made by the PostgreSQL team. A good overview of why and what you can do instead can be found her...
iOS UIImagePickerController result image orientation after upload
...size.height,
CGImageGetBitsPerComponent(self.CGImage), 0,
CGImageGetColorSpace(self.CGImage),
CGImageGetBitmapInfo(self.CGImage));
CGContextConcatCTM(ctx, transf...
Difference between Hashing a Password and Encrypting it
...th the specific property that not only the hash be non-reversable BUT ALSO computationally impractical to generate ANY other string that generates the same hash.
– Tall Jeff
Nov 28 '08 at 21:25
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Measuring execution time of a function in C++
...n my C++ program to execute on Linux . Afterwards, I want to make a speed comparison . I saw several time function but ended up with this from boost. Chrono:
...
What is the JavaScript version of sleep()?
... a better way to engineer a sleep in JavaScript than the following pausecomp function ( taken from here )?
78 Answers
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Correct idiom for managing multiple chained resources in try-with-resources block?
...er(new FileWriter(file))) {
bw.write(text);
}
For me, the best thing coming to Java from traditional C++ 15 years ago was that you could trust your program. Even if things are in the muck and going wrong, which they often do, I want the rest of the code to be on best behaviour and smelling of ...
Why is null an object and what's the difference between null and undefined?
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SortedList, SortedDictionary and Dictionary
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