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How to sort a dataframe by multiple column(s)
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rather than using the name of the column (and with() for easier/more direct access).
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What are inline namespaces for?
...ief, succinct example of a situation where an inline namespace is needed and where it is the most idiomatic solution?
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How do you convert a byte array to a hexadecimal string, and vice versa?
How can you convert a byte array to a hexadecimal string, and vice versa?
45 Answers
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C++ unordered_map using a custom class type as the key
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A hash function; this must be a class that overrides operator() and calculates the hash value given an object of the key-type. One particularly straight-forward way of doing this is to specialize the std::hash template for your key-type.
A comparison function for equality; this is require...
Default string initialization: NULL or Empty? [closed]
... strings to NULL, with the thinking that NULL means the absence of a value and "" or String.Empty is a valid value. I have seen more examples lately of code where String.Empty is considered the default value or represents no value. This strikes me as odd, with the newly added nullable types in c# ...
Getting the first and last day of a month, using a given DateTime object
I want to get the first day and last day of the month where a given date lies in. The date comes from a value in a UI field.
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Disable Auto Zoom in Input “Text” tag - Safari on iPhone
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The browser will zoom if the font-size is less than 16px and the default font-size for form elements is 11px (at least in Chrome and Safari).
Additionally, the select element needs to have the focus pseudo-class attached.
input[type="color"],
input[type="date"],
input[type="datet...
What's the difference between fill_parent and wrap_content?
In Android, when layout out widgets, what's the difference between fill_parent ( match_parent in API Level 8 and higher) and wrap_content ?
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What is the bower (and npm) version syntax?
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In a nutshell, the syntax for Bower version numbers (and NPM's) is called SemVer, which is short for 'Semantic Versioning'. You can find documentation for the detailed syntax of SemVer as used in Bower and NPM on the API for the semver parser within Node/npm. You can learn more...
How do I check CPU and Memory Usage in Java?
I need to check CPU and memory usage for the server in java, anyone know how it could be done?
15 Answers
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