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Returning the product of a list
...rt numpy as np
import numexpr as ne
# from functools import reduce # python3 compatibility
a = range(1, 101)
%timeit reduce(lambda x, y: x * y, a) # (1)
%timeit reduce(mul, a) # (2)
%timeit np.prod(a) # (3)
%timeit ne.evaluate("prod(a)") # (4)
In t...
Remove the last three characters from a string
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read last 3 characters from string [Initially asked question]
You can use string.Substring and give it the starting index and it will get the substring starting from given index till end.
myString.Substring(myString.Length-3)
...
Simultaneously merge multiple data.frames in a list
...question was marked as a duplicate of this one so I answer here, using the 3 sample data frames below:
x <- data.frame(i = c("a","b","c"), j = 1:3, stringsAsFactors=FALSE)
y <- data.frame(i = c("b","c","d"), k = 4:6, stringsAsFactors=FALSE)
z <- data.frame(i = c("c","d","a"), l = 7:9, stri...
Why are Python lambdas useful? [closed]
...where you can pass functions to other functions to do stuff. Example:
mult3 = filter(lambda x: x % 3 == 0, [1, 2, 3, 4, 5, 6, 7, 8, 9])
sets mult3 to [3, 6, 9], those elements of the original list that are multiples of 3. This is shorter (and, one could argue, clearer) than
def filterfunc(x):
...
How to format a phone number with jQuery
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Simple: http://jsfiddle.net/Xxk3F/3/
$('.phone').text(function(i, text) {
return text.replace(/(\d{3})(\d{3})(\d{4})/, '$1-$2-$3');
});
Or: http://jsfiddle.net/Xxk3F/1/
$('.phone').text(function(i, text) {
return text.replace(/(\d\d\d)(\d\d\d)(...
What's the best way to send a signal to all members of a process group?
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33 Answers
33
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Difference between List, List, List, List, and List
...Could e.g. be used by a method that is returning the length of the list.
3) T, E and U are the same, but people tend to use e.g. T for type, E for Element, V for value and K for key. The method that compiles says that it took an array of a certain type, and returns an array of the same type.
4) Y...
NumPy array initialization (fill with identical values)
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325
NumPy 1.8 introduced np.full(), which is a more direct method than empty() followed by fill()...
Integrate ZXing in Android Studio
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234
I was integrating ZXING into an Android application and there were no good sources for the inpu...
Why is [1,2] + [3,4] = “1,23,4” in JavaScript?
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13 Answers
13
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