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sqlite3-ruby install error on Ubuntu
I have the following error during sqlite3-ruby install:
19 Answers
19
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Pandas index column title or name
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394
You can just get/set the index via its name property
In [7]: df.index.name
Out[7]: 'Index Tit...
Finding the mode of a list
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vinzee
7,44399 gold badges3131 silver badges4848 bronze badges
answered Jan 24 '15 at 20:08
David DaoDavid Dao
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Ruby - elegantly convert variable to an array if not an array already
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153
[*foo] or Array(foo) will work most of the time, but for some cases like a hash, it messes it up...
php中json_decode()和json_encode()的使用方法 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...Example #1 json_decode() 的例子
<?php
$json = '{"a":1,"b":2,"c":3,"d":4,"e":5}';
var_dump(json_decode($json));
var_dump(json_decode($json, true));
?>
上例将输出：
object(stdClass)#1 (5) {
["a"] => int(1)
["b"] => int(2)
["c"] => int(3)
["d"] => int(4)
["e"] => i...
What does -1 mean in numpy reshape?
...numpy allow us to give one of new shape parameter as -1 (eg: (2,-1) or (-1,3) but not (-1, -1)). It simply means that it is an unknown dimension and we want numpy to figure it out. And numpy will figure this by looking at the 'length of the array and remaining dimensions' and making sure it satisfi...
NULL values inside NOT IN clause
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Query A is the same as:
select 'true' where 3 = 1 or 3 = 2 or 3 = 3 or 3 = null
Since 3 = 3 is true, you get a result.
Query B is the same as:
select 'true' where 3 <> 1 and 3 <> 2 and 3 <> null
When ansi_nulls is on, 3 <> null is UNKNOWN,...
Insert a line at specific line number with sed or awk
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243
sed -i '8i8 This is Line 8' FILE
inserts at line 8
8 This is Line 8
into file FILE
-i doe...
Python Remove last 3 characters of a string
I'm trying to remove the last 3 characters from a string in python, I don't know what these characters are so I can't use rstrip , I also need to remove any white space and convert to upper-case
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What is the difference among col-lg-*, col-md-* and col-sm-* in Bootstrap?
...efore, the auto-layout columns fill equal width across the row.
Bootstrap 3
The Bootstrap 3 grid comes in 4 tiers (or "breakpoints")...
Extra small (for smartphones .col-xs-*)
Small (for tablets .col-sm-*)
Medium (for laptops .col-md-*)
Large (for laptops/desktops .col-lg-*).
These grid sizes ena...