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How to check that a string is an int, but not a double, etc.?
PHP has an intval() function that will convert a string to an integer. However I want to check that the string is an integer beforehand, so that I can give a helpful error message to the user if it's wrong. PHP has is_int() , but that returns false for string like "2" .
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Referring to a Column Alias in a WHERE Clause
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How to recover stashed uncommitted changes
I had some uncommitted changes in my development branch and I stashed them using git stash , but there were some changes which were very important among those stashed ones. Is there any way to get back those changes?
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What's the difference between QMainWindow, QWidget and QDialog?
What's the difference between QMainWindow, QWidget and QDialog?
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How do I check if an object has a specific property in JavaScript?
How do I check if an object has a specific property in JavaScript?
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Will console.log reduce JavaScript execution performance?
Will use of the debugging feature console.log reduce JavaScript execution performance? Will it affect the speed of script execution in production environments?
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What are the most-used vim commands/keypresses?
I'm a Ruby programming trying to switch from Textmate to MacVim, and I'm having trouble wading through the gargantuan lists of things you can do in VIM and all of the keypresses for them. I'm tired of hearing "You can use 'I' for inserting text, or 'a' for appending text after the character, or 'A' ...
Replacing NAs with latest non-NA value
In a data.frame (or data.table), I would like to "fill forward" NAs with the closest previous non-NA value. A simple example, using vectors (instead of a data.frame ) is the following:
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Convert column classes in data.table
I have a problem using data.table: How do I convert column classes? Here is a simple example: With data.frame I don't have a problem converting it, with data.table I just don't know how:
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“Code too large” compilation error in Java
Is there any maximum size for code in Java? I wrote a function with more than 10,000 lines. Actually, each line assigns a value to an array variable.
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