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“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP
... can be used to detect if a variable has been already initialized. Additionally and more ideal is the solution of empty() since it does not generate a warning or error message if the variable is not initialized.
From PHP documentation:
No warning is generated if the variable does not exist. T...
How to delete files/subfolders in a specific directory at the command prompt in Windows
Say, there is a variable called %pathtofolder% , as it makes it clear it is a full path of a folder.
15 Answers
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The purpose of Model View Projection Matrix
...d space to camera space, projection from camera to screen.
If you compose all three, you can use the one result to map all the way from object space to screen space, making you able to work out what you need to pass on to the next stage of a programmable pipeline from the incoming vertex positions....
Should we use Nexus or Artifactory for a Maven Repo?
...out Artifactory but here are my reasons for using Nexus:
Dead simple install (and since 1.2, dead simple upgrade, too)
Very good web UI
Easy to maintain, almost no administrative overhead
Provides you with RSS feeds of recently installed, broken artifacts and errors
It can group several repositori...
EF Code First foreign key without navigation property
...class and sql is just the above SQL command as string.
Be aware that with all this EF has no clue that ParentId is a foreign key that describes a relationship. EF will consider it only as an ordinary scalar property. Somehow all the above is only a more complicated and slower way compared to just o...
Mac OS X - EnvironmentError: mysql_config not found
...
Ok, well, first of all, let me check if I am on the same page as you:
You installed python
You did brew install mysql
You did export PATH=$PATH:/usr/local/mysql/bin
And finally, you did pip install MySQL-Python (or pip3 install mysqlclient if...
Firebug-like debugger for Google Chrome
...ntrospection, I can do it with Firebug. Now with IE8's new developer mode, all the major browsers have builtin dev modes. Good times.
– guns
Apr 27 '09 at 9:32
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Django: ImproperlyConfigured: The SECRET_KEY setting must not be empty
... Refactor to avoid circular dependency. The exact solution is really fairly specific to your own code.
– Sam Svenbjorgchristiensensen
Feb 17 '14 at 22:10
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What are the differences between local branch, local tracking branch, remote branch and remote track
I just started using Git and I got really confused between different branches. Can anyone help me to figure out what the following branch types are?
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Can constructors throw exceptions in Java?
Are constructors allowed to throw exceptions?
6 Answers
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