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Fast permutation -> number -> permutation mapping algorithms

...ake of an example, let's say, 7 elements, 1234567. I know there are 7! = 5040 permutations possible of these 7 elements. 1...
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Fastest way to convert string to integer in PHP

...s -------------------------------------------- (int) "123": 0.55029 intval("123"): 1.0115 (183%) (int) "0": 0.42461 intval("0"): 0.95683 (225%) (int) int: 0.1502 intval(int): 0.65716 (438%) (int) array("a...
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What's the fastest way to merge/join data.frames in R?

...he first example sqldf is 3x slower than data.table and in the second its 200x faster than plyr and 100 times faster than data.table. Below we show the input code, the output timings for the merge and the output timings for the aggregate. Its also worthwhile noting that sqldf is based on a databa...
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What is the most pythonic way to check if an object is a number?

...cimal import Decimal ... from fractions import Fraction ... for n in [2, 2.0, Decimal('2.0'), complex(2, 0), Fraction(2, 1), '2']: ... print(f'{n!r:>14} {isinstance(n, Number)}') 2 True 2.0 True Decimal('2.0') True (2+0j) True Fraction(2, 1) True ...
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How to take column-slices of dataframe in pandas

... 10 Answers 10 Active ...
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Generate colors between red and green for a power meter?

... 203 This should work - just linearly scale the red and green values. Assuming your max red/green/bl...
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How can I scale the content of an iframe?

...ra and Safari if you change the CSS to: <style> #wrap { width: 600px; height: 390px; padding: 0; overflow: hidden; } #frame { width: 800px; height: 520px; border: 1px solid black; } #frame { -ms-zoom: 0.75; -moz-transform: scale(0.75); -moz-transform-origin...
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Why `null >= 0 && null

...ncrements the value of a variable by 1 if its type is number and assigns 0 to the variable if not, where the variable is initially null or undefined . ...
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How to replace NaN values by Zeroes in a column of a Pandas Dataframe?

... 807 I believe DataFrame.fillna() will do this for you. Link to Docs for a dataframe and for a Seri...
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mfc里面的140种颜色宏 - C/C++ - 清泛网 - 专注C/C++及内核技术

mfc里面的140种颜色宏MFC编码是需要配色的,可以参考使用。#pragma once #define CLR_LIGHTPINK RGB(255, 182, 193) ...mfc编码时需要配色的,可以参考使用。 #pragma once #define CLR_LIGHTPINK RGB(255, 182, 193) // 浅粉红 #...