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How to change the background color of a UIButton while it's highlighted?
...hlighted UIButton (for example when a user has his finger on the button) and I need to change the background color while the button is highlighted (so while the finger of the user is still on the button).
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Difference between Select and ConvertAll in C#
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Select is a LINQ extension method and works on all IEnumerable<T> objects whereas ConvertAll is implemented only by List<T>. The ConvertAll method exists since .NET 2.0 whereas LINQ was introduced with 3.5.
You should favor Select over ConvertAll...
What MySQL data type should be used for Latitude/Longitude with 8 decimal places?
I'm working with map data, and the Latitude/Longitude extends to 8 decimal places. For example:
8 Answers
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How to convert a column number (e.g. 127) into an Excel column (e.g. AA)
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For better understanding, I would replace the 65 with 'A'
– Stef Heyenrath
Nov 11 '11 at 11:12
11
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Is there a performance gain in using single quotes vs double quotes in ruby?
...gle quotes in ruby decreases performance in any meaningful way in ruby 1.8 and 1.9.
14 Answers
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How to extract one column of a csv file
...ou are a lucky guy using GNU Tools in Windows, you can execute the same comand as @IgorMikushkin as follows: gawk -F"|" "{print $13}" files*.csv
– Elidio Marquina
May 25 '17 at 18:33
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Simulate delayed and dropped packets on Linux
I would like to simulate packet delay and loss for UDP and TCP on Linux to measure the performance of an application. Is there a simple way to do this?
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Finding a branch point with Git?
I have a repository with branches master and A and lots of merge activity between the two. How can I find the commit in my repository when branch A was created based on master?
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How to reset postgres' primary key sequence when it falls out of sync?
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-- Login to psql and run the following
-- What is the result?
SELECT MAX(id) FROM your_table;
-- Then run...
-- This should be higher than the last result.
SELECT nextval('your_table_id_seq');
-- If it's not higher... run this set the sequ...
Why covariance and contravariance do not support value type
...or not.
You might want to read Eric Lippert's blog post on representation and identity for more on this topic in general.
EDIT: Having reread Eric's blog post myself, it's at least as much about identity as representation, although the two are linked. In particular:
This is why covariant and ...