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Bubble Sort Homework
...cient or readable.
In the for loop, you use the variable element. Technically, element is not an element; it's a number representing a list index. Also, it's quite long. In these cases, just use a temporary variable name, like i for "index".
for i in range(0, length):
The range command can also ...
Delete all records in a table of MYSQL in phpMyAdmin
I use wampserver 2.2. When I want to delete all records of a table in phpMyAdmin (select all) it deletes only one record not all records. Why it does not delete all records?
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Double negation (!!) in javascript - what is the purpose? [duplicate]
...ue
null to true
+0 to true
-0 to true
'' to true
NaN to true
false to true
All other expressions to false
Then the other ! negates it again. A concise cast to boolean, exactly equivalent to ToBoolean simply because ! is defined as its negation. It’s unnecessary here, though, because it’s only ...
Is there any performance gain in indexing a boolean field?
...udes a WHERE isok=1 . As the name implies, isok is a boolean field (actually a TINYINT(1) UNSIGNED that is set to 0 or 1 as needed).
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What is a 'multi-part identifier' and why can't it be bound?
I continually get these errors when I try to update tables based on another table. I end up rewriting the query, change the order of joins, change some groupings and then it eventually works, but I just don't quite get it.
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PHP - Get key name of array value
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array_filter() can be used if you need to return all matching results instead of just the first matching one, as it preserves keys.
– Mike Lyons
Nov 27 '14 at 1:40
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How to count number of files in each directory?
I am able to list all the directories by
17 Answers
17
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Allow CORS REST request to a Express/Node.js application on Heroku
...de on a clean ExpressJS app and it works just fine.
Try move your app.use(allowCrossDomain) to the top of configure function.
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Automatically expanding an R factor into a collection of 1/0 indicator variables for every factor le
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And if you want to convert all factor columns, you can use: model.matrix(~., data=iris)[,-1]
– user890739
Jan 5 '16 at 0:32
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Differences between Emacs and Vim
...and weeks till you will be happy with it and then you will learn new stuff all the time. You will be annoyed when you don't have access to it and constantly change your config. You won't be able to use other peoples emacs versions easily and it won't just be installed. It uses Lisp, which is great. ...