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Create a pointer to two-dimensional array
I need a pointer to a static 2-dimensional array. How is this done?
10 Answers
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Sending a message to nil in Objective-C
As a Java developer who is reading Apple's Objective-C 2.0 documentation: I wonder what " sending a message to nil " means - let alone how it is actually useful. Taking an excerpt from the documentation:
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Why #define TRUE (1==1) in a C boolean macro instead of simply as 1?
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8 Answers
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Ruby 2.0.0p0 IRB warning: “DL is deprecated, please use Fiddle”
I just uninstalled my older versions of Ruby, removed all of my gems
(including Rails), and installed Ruby 2.0. In other words, a totally clean re-install. Upon starting IRB, I received this message:
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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
When using summarise with plyr 's ddply function, empty categories are dropped by default. You can change this behavior by adding .drop = FALSE . However, this doesn't work when using summarise with dplyr . Is there another way to keep empty categories in the result?
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Bootstrap 3 modal vertical position center
This is a two part question:
34 Answers
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What does the “|” (single pipe) do in JavaScript?
Why does 0.5 | 0 return zero, but any integer (including negative) returns the input integer? What does the single pipe ("|") do?
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ActiveRecord: size vs count
In Rails, you can find the number of records using both Model.size and Model.count . If you're dealing with more complex queries is there any advantage to using one method over the other? How are they different?
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What is sr-only in Bootstrap 3?
What is the class sr-only used for? Is it important or can I remove it? Works fine without.
6 Answers
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How to convert ASCII code (0-255) to its corresponding character?
How can I convert, in Java, the ASCII code (which is an integer from [0, 255] range) to its corresponding ASCII character?
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