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How can the Euclidean distance be calculated with NumPy?

... There's a function for that in SciPy. It's called Euclidean. Example: from scipy.spatial import distance a = (1, 2, 3) b = (4, 5, 6) dst = distance.euclidean(a, b) share | ...
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Does python have an equivalent to Java Class.forName()?

...takes a fully qualified class name and returns the class, however you have all the pieces needed to build that, and you can connect them together. One bit of advice though: don't try to program in Java style when you're in python. If you can explain what is it that you're trying to do, maybe we ca...
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How to check if a variable is set in Bash?

... (Usually) The right way if [ -z ${var+x} ]; then echo "var is unset"; else echo "var is set to '$var'"; fi where ${var+x} is a parameter expansion which evaluates to nothing if var is unset, and substitutes the string x otherw...
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Will iOS launch my app into the background if it was force-quit by the user?

... Unlike the application:didReceiveRemoteNotification: method, which is called only when your app is running in the foreground, the system calls this method when your app is running in the foreground or background. In addition, if you enabled the remote notifications background mode, the sys...
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Speed up the loop operation in R

...Biggest problem and root of ineffectiveness is indexing data.frame, I mean all this lines where you use temp[,]. Try to avoid this as much as possible. I took your function, change indexing and here version_A dayloop2_A <- function(temp){ res <- numeric(nrow(temp)) for (i in 1:nrow(te...
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Something like 'contains any' for Java set?

... Actually it will short-circuit as soon as it finds the first common element – Xipo Dec 15 '16 at 10:54 3 ...
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Manually raising (throwing) an exception in Python

... How do I manually throw/raise an exception in Python? Use the most specific Exception constructor that semantically fits your issue. Be specific in your message, e.g.: raise ValueError('A very specific bad thing happened.') Don't ...
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How to specify maven's distributionManagement organisation wide?

...s to create a simple parent pom file project (with packaging 'pom') generically for all projects from your organization. <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="...
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Why does GCC generate 15-20% faster code if I optimize for size instead of speed?

... gcc-4.8 1.53s 1.52s -Os In some cases you can alleviate the effect of disadvantageous optimizations by asking gcc to optimize for your particular processor (using options -mtune=native or -march=native): Processor Compiler Time (-O2 -mtune=native) Time (-Os...
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Convert string to symbol-able in ruby

Symbols are usually represented as such 7 Answers 7 ...