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Automatically expanding an R factor into a collection of 1/0 indicator variables for every factor le
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And if you want to convert all factor columns, you can use: model.matrix(~., data=iris)[,-1]
– user890739
Jan 5 '16 at 0:32
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Are HLists nothing more than a convoluted way of writing tuples?
I am really interested in finding out where the differences are, and more generally, to identify canonical use cases where HLists cannot be used (or rather, don't yield any benefits over regular lists).
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Pointer vs. Reference
... Explain what you mean by arithmetic. A new user may not understand that you want to adjust what the pointer is pointing at.
– Martin York
Sep 22 '08 at 16:30
7
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Why does casting int to invalid enum value NOT throw exception?
...ted .NET. An enum is backed by another value type (int, short, byte, etc), and so it can actually have any value that is valid for those value types.
I personally am not a fan of the way this works, so I made a series of utility methods:
/// <summary>
/// Utility methods for enum values. Thi...
typedef fixed length array
...used as a function argument, it will be passed by reference, not by value, and the sizeof for it will then be wrong.
A better solution would be
typedef struct type24 { char x[3]; } type24;
You probably also want to be using unsigned char instead of char, since the latter has implementation-defin...
Reading and writing binary file
...r only stores a couple of ASCII characters from the first line in the file and nothing else.
7 Answers
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What is default color for text in textview?
I set the color to red , and after that I want to set the color again back to default, but I do not know what is default color, does anyone knows ?
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Good way of getting the user's location in Android
Getting the user's current location within a threshold ASAP and at the same time conserve battery.
10 Answers
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How can I generate random number in specific range in Android? [duplicate]
I want to generate random number in a specific range. (Ex. Range Between 65 to 80)
2 Answers
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Default value of a type at Runtime [duplicate]
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There's really only two possibilities: null for reference types and new myType() for value types (which corresponds to 0 for int, float, etc) So you really only need to account for two cases:
object GetDefaultValue(Type t)
{
if (t.IsValueType)
return Activator.CreateInstance(...