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Pandas selecting by label sometimes return Series, sometimes returns DataFrame
In Pandas, when I select a label that only has one entry in the index I get back a Series, but when I select an entry that has more then one entry I get back a data frame.
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Number of lines in a file in Java
...ly need to know the number of lines in these files, usually I open them up and read them line by line until I reach the end of the file
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Simplest code for array intersection in javascript
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Use a combination of Array.prototype.filter and Array.prototype.includes:
array1.filter(value => array2.includes(value))
For older browsers, with Array.prototype.indexOf and without an arrow function:
array1.filter(function(n) {
return array2.indexOf(n) !== ...
How can one print a size_t variable portably using the printf family?
I have a variable of type size_t , and I want to print it using printf() . What format specifier do I use to print it portably?
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Iterate over the lines of a string
... the main script confirms the three functions are equivalent. With timeit (and a * 100 for foo to get substantial strings for more precise measurement):
$ python -mtimeit -s'import asp' 'list(asp.f3())'
1000 loops, best of 3: 370 usec per loop
$ python -mtimeit -s'import asp' 'list(asp.f2())'
1000 ...
Using reflect, how do you set the value of a struct field?
...ction is to see how the core Go developers use it. For example, the Go fmt and json packages. The package documentation has links to the source code files under the heading Package files.
The Go json package marshals and unmarshals JSON from and to Go structures.
Here's a step-by-step example wh...
php发送get、post请求的几种方法 - 更多技术 - 清泛网 - 专注C/C++及内核技术
php发送get、post请求的几种方法方法1: 用file_get_contents 以get方式获取内容<?php$url='http: www.domain.com ';$html = file_get_contents($url);echo $...方法1：用file_get_contents 以get方式获取内容
<?php
$url='http://www.domain.com/';
$html = file_get_contents(...
Relationship between SciPy and NumPy
...numpy as _num
from numpy import oldnumeric
from numpy import *
from numpy.random import rand, randn
from numpy.fft import fft, ifft
from numpy.lib.scimath import *
The log10 function you get in scipy comes from numpy.lib.scimath. Looking at that code, it says:
"""
Wrapper functions to more user-f...
Hiding user input on terminal in Linux script
... answered Nov 30 '10 at 17:46
Andreas WongAndreas Wong
53.4k1818 gold badges9898 silver badges118118 bronze badges
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Foreign Key to non-primary key
I have a table which holds data, and one of those rows needs to exist in another table. So, I want a foreign key to maintain referential integrity.
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