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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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Selecting data frame rows based on partial string match in a column
I want to select rows from a data frame based on partial match of a string in a column, e.g. column 'x' contains the string "hsa". Using sqldf - if it had a like syntax - I would do something like:
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Better way to sum a property value in an array
I have something like this:
16 Answers
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How are multi-dimensional arrays formatted in memory?
In C, I know I can dynamically allocate a two-dimensional array on the heap using the following code:
6 Answers
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Given an RGB value, how do I create a tint (or shade)?
Given an RGB value, like 168, 0, 255 , how do I create tints (make it lighter) and shades (make it darker) of the color?
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C++: Rounding up to the nearest multiple of a number
OK - I'm almost embarrassed posting this here (and I will delete if anyone votes to close) as it seems like a basic question.
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Does .NET provide an easy way convert bytes to KB, MB, GB, etc.?
Just wondering if .NET provides a clean way to do this:
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JavaScript function similar to Python range()
Is there a function in JavaScript similar to Python's range() ?
23 Answers
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How to create a video from images with FFmpeg?
This line worked fine but I want to create a video file from images in another folder.
Image names in my folder are:
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How do I know the script file name in a Bash script?
How can I determine the name of the Bash script file inside the script itself?
23 Answers
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