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Convert data.frame columns from factors to characters
... data.frame(lapply(bob, as.character), stringsAsFactors=FALSE)
This will convert all variables to class "character", if you want to only convert factors, see Marek's solution below.
As @hadley points out, the following is more concise.
bob[] <- lapply(bob, as.character)
In both cases, lapp...
How to convert java.util.Date to java.sql.Date?
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tl;dr
How to convert java.util.Date to java.sql.Date?
Don’t. Both classes are outmoded.
Use java.time classes instead of legacy java.util.Date & java.sql.Date with JDBC 4.2 or later.
Convert to/from java.time if inter-operating wi...
Why does Convert.ToString(null) return a different value if you cast null?
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There are 2 overloads of ToString that come into play here
Convert.ToString(object o);
Convert.ToString(string s);
The C# compiler essentially tries to pick the most specific overload which will work with the input. A null value is convertible to any reference type. In this case ...
Empty arrays seem to equal true and false at the same time
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@Devy all objects in JavaScript are truthy, so the convert any objects to Boolean is true. See 2ality.com/2013/08/objects-truthy.html
– Thomson
Oct 17 '16 at 21:27
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How to specialize std::hash::operator() for user-defined type in unordered containers?
... h is an expression of type H or const H, and k is an expression of a type convertible to (possibly const) Key, then h(k) is a valid expression with type size_t.
If h is an expression of type H or const H, and u is an lvalue of type Key, then h(u) is a valid expression with type size_t which does no...
ProcessStartInfo hanging on “WaitForExit”? Why?
...in a similar situation. I was redirecting StandardError for no reason when converting with ffmpeg in a process, it was writting enough in the StandardError stream to create a deadlock.
– Léon Pelletier
Oct 1 '12 at 7:29
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How do I invert BooleanToVisibilityConverter?
I'm using a BooleanToVisibilityConverter in WPF to bind the Visibility property of a control to a Boolean . This works fine, but I'd like one of the controls to hide if the boolean is true , and show if it's false .
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JavaScriptSerializer - JSON serialization of enum as string
...enum as a string in my json without having to create a custom JavaScriptConverter ? Perhaps there's an attribute that I could decorate the enum definition, or object property, with?
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C compiler for Windows? [closed]
... so much of an issue. Also, I've never used them but there are file format converter tools.
– BCS
Apr 23 '09 at 17:52
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Any reason why scala does not explicitly support dependent types?
...plicated that it is hard to see the laws, the value
level expressions are converted (automatically but still) to type level things and
you need to trust that conversion as well.
There is room for error in all of this which kinda defies the purpose of compiler acting as
a proof assistant.
(EDITE...