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Convert a matrix to a 1 dimensional array
...do as.vector() on the matrix. You might want to transpose the matrix first if you want it by rows or columns.
> m=matrix(1:12,3,4)
> m
[,1] [,2] [,3] [,4]
[1,] 1 4 7 10
[2,] 2 5 8 11
[3,] 3 6 9 12
> as.vector(m)
[1] 1 2 3 4 5 6 7 8 9 10 11 1...
Safely remove migration In Laravel
...me.php
Reset the composer autoload files: composer dump-autoload
Relax
If you did run the migration (php artisan migrate), you may do this:
a) Run migrate:rollback - it is the right way to undo the last migration (Thnx @Jakobud)
b) If migrate:rollback does not work, do it manually (I remember ...
Extract a number from a string (JavaScript)
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For this specific example,
var thenum = thestring.replace( /^\D+/g, ''); // replace all leading non-digits with nothing
in the general case:
thenum = "foo3bar5".match(/\d+/)[0] // "3"
Since this answer gained popularity for some r...
How to use NULL or empty string in SQL
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If you need it in SELECT section can use like this.
SELECT ct.ID,
ISNULL(NULLIF(ct.LaunchDate, ''), null) [LaunchDate]
FROM [dbo].[CustomerTable] ct
you can replace the null with your substitution ...
Relational Database Design Patterns? [closed]
...oyees, accounts, shipping, purchases, etc), Volume 2 contains industry specific data models (accounting, healthcare, etc), Volume 3 provides data model patterns.
Finally, while this book is ostensibly about UML and Object Modelling, Peter Coad's Modeling in Color With UML provides an "archetype" dr...
How to set a cookie for another domain
Say I have a website called a.com , and when a specific page of this site is loaded, say page link, I like to set a cookie for another site called b.com , then redirect the user to b.com .
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How to convert/parse from String to char in java?
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If your string contains exactly one character the simplest way to convert it to a character is probably to call the charAt method:
char c = s.charAt(0);
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echo that outputs to stderr
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FYI: if you want to format or do anything besides simply echo the string then you'll have to move the redirect back to the end. For example errcho(){ >&2 echo $@|pr -To5;} won't work. To do something like that you'll have...
X-UA-Compatible is set to IE=edge, but it still doesn't stop Compatibility Mode
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If you need to override IE's Compatibility View Settings for intranet sites you can do so in the web.config (IIS7) or through the custom HTTP headers in the web site's properties (IIS6) and set X-UA-Compatible there. The met...
Rails :include vs. :joins
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.joins will just joins the tables and brings selected fields in return. if you call associations on joins query result, it will fire database queries again
:includes will eager load the included associations and add them in memory. :includes loads all the included tables attributes. If you call ...