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Equation for testing if a point is inside a circle
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It may help some less math minded folks to see the square root operation used to measure distance compared against the radius. I realize that's not optimal, but as your answer is formatted more like an equation than code perhaps it makes more sense? Just a suggestion.
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Why do I get access denied to data folder when using adb?
... want to browse everything on your device.
You need to have a phone with root access in order to browse the data folder on an Android phone. That means either you have a developer device (ADP1 or an ION from Google I/O) or you've found a way to 'root' your phone some other way.
You need to be runn...
What is the fastest way to compute sin and cos together?
...nd be aware that using this method involves computing a power and a square root, so if performance is important, make sure to verify that this is actually faster than computing the other trig function directly.
– Tyler McHenry
Apr 21 '10 at 14:11
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Rails.env vs RAILS_ENV
...ewise, you can use RAILS_DEFAULT_LOGGER to get the current logger or RAILS_ROOT to get the path to the root folder.
Starting from Rails 2.x, Rails introduced the Rails module with some special methods:
Rails.root
Rails.env
Rails.logger
This isn't just a cosmetic change. The Rails module offers ...
Semicolons superfluous at the end of a line in shell scripts?
... on terminal or in shell script.
See the below examples:
On terminal:
[root@server test]# ls;pwd;
On shell script:
[root@server test]# cat test4.sh
echo "Current UserName:"
whoami
echo -e "\nCurrent Date:";date;
[root@server test]#
But I am not agree with the comment that & is equi...
Simulate CREATE DATABASE IF NOT EXISTS for PostgreSQL?
I want to create a database which does not exist through JDBC. Unlike MySQL, PostgreSQL does not support create if not exists syntax. What is the best way to accomplish this?
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Count the occurrences of DISTINCT values
I am trying to find a MySQL query that will find DISTINCT values in a particular field, count the number of occurrences of that value and then order the results by the count.
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Received fatal alert: handshake_failure through SSLHandshakeException
...certificate trust path between the certificate issued to the server, and a root CA. In most cases, this is because the root CA's certificate is absent in the trust store, leading to the situation where a certificate trust path cannot exist; the certificate is essentially untrusted by the client. Bro...
How to export a Vagrant virtual machine to transfer it
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Does the "clean way" account for databases (mySQL, Wordpress) that might be inside the vm? How can that be synced over to the other pc?
– kevllar
Feb 17 '16 at 4:33
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Is storing a delimited list in a database column really that bad?
...ient table-scan. May have to resort to regular expressions, for example in MySQL:
idlist REGEXP '[[:<:]]2[[:>:]]'*
Hard to count elements in the list, or do other aggregate queries.
Hard to join the values to the lookup table they reference.
Hard to fetch the list in sorted order.
To solve th...