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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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Why does C++ not allow inherited friendship?
Why is friendship not at least optionally inheritable in C++? I understand transitivity and reflexivity being forbidden for obvious reasons (I say this only to head off simple FAQ quote answers), but the lack of something along the lines of virtual friend class Foo; puzzles me. Does anyone know ...
Insert into … values ( SELECT … FROM … )
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is it Necessary that we insert into all columns of the table
– maheshmnj
Feb 24 at 7:22
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How to overload __init__ method based on argument type?
Let's say I have a class that has a member called data which is a list.
10 Answers
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Difference between `set`, `setq`, and `setf` in Common Lisp?
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Originally, in Lisp, there were no lexical variables -- only dynamic ones. And
there was no SETQ or SETF, just the SET function.
What is now written as:
(setf (symbol-value '*foo*) 42)
was written as:
(set (quote *foo*) 42)
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Difference between := and = operators in Go
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@KrupalShah the link to the docs literally says that - "It is shorthand for a regular variable declaration with initializer expressions but no types:" golang.org/ref/spec#Short_variable_declarations
– akshaynagpal
Jun 16 '...
Delete a key from a MongoDB document using Mongoose
...de-mongodb-native driver. Each model has a collection object that contains all the methods that node-mongodb-native offers. So you can do the action in question by this:
User.collection.update({_id: user._id}, {$unset: {field: 1 }});
Since version 2.0 you can do:
User.update({_id: user._id}, {$u...
Extracting extension from filename in Python
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@klingt.net Well, in that case, .asd is really the extension!! If you think about it, foo.tar.gz is a gzip-compressed file (.gz) which happens to be a tar file (.tar). But it is a gzip file in first place. I wouldn't expect it to return the dual extension at all.
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What are the most common naming conventions in C?
...I follow the GTK+ coding convention, which can be summarized as follows:
All macros and constants in caps: MAX_BUFFER_SIZE, TRACKING_ID_PREFIX.
Struct names and typedef's in camelcase: GtkWidget, TrackingOrder.
Functions that operate on structs: classic C style: gtk_widget_show(), tracking_order_p...
Delete all local changesets and revert to tree
I'm using Mercurial and I've got into a terrible mess locally, with three heads. I can't push, and I just want to delete all my local changes and commits and start again with totally clean code and a clean history.
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