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How do I delete an exported environment variable?
Before installing gnuplot, I set the environment variable GNUPLOT_DRIVER_DIR = /home/gnuplot/build/src . During the installation, something went wrong.
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Global and local variables in R
I am a newbie for R, and I am quite confused with the usage of local and global variables in R.
3 Answers
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Is an index needed for a primary key in SQLite?
When an integer column is marked as a primary key in an SQLite table, should an index be explicitly created for it as well? SQLite does not appear to automatically create an index for a primary key column, but perhaps it indexes it anyway, given its purpose? (I will be searching on that column all t...
Check if a value is within a range of numbers
I want to check if a value is in an accepted range. If yes, to do something; otherwise, something else.
7 Answers
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NSDefaultRunLoopMode vs NSRunLoopCommonModes
Whenever I try to download a big file behind UIScrollView , MPMapView or something, the downloading process gets halted as soon as I touch iPhone screen. Thankfully, an awesome blog post by Jörn suggests an alternative option, using NSRunLoopCommonModes for connection.
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Converting dict to OrderedDict
I am having some trouble using the collections.OrderedDict class. I am using Python 2.7 on Raspbian, the Debian distro for Raspberry Pi. I am trying to print two dictionaries in order for comparison (side-by-side) for a text-adventure. The order is essential to compare accurately.
No matter what I...
How to change the default collation of a table?
creates a table with the default collation latin1_general_ci ;
4 Answers
4
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Sending a notification from a service in Android
I have a service running, and would like to send a notification. Too bad, the notification object requires a Context , like an Activity , and not a Service .
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How to do an INNER JOIN on multiple columns
I'm working on a homework project and I'm supposed to perform a database query which finds flights either by the city name or the airport code, but the flights table only contains the airport codes so if I want to search by city I have to join on the airports table.
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PHP Timestamp into DateTime
Do you know how I can convert this to a strtotime, or a similar type of value to pass into the DateTime object?
4 Answer...