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Selecting only numeric columns from a data frame
Suppose, you have a data.frame like this:
11 Answers
11
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MySQL - ORDER BY values within IN()
... direction after each part. The equality check would have a value of 1 and all the rest would be 0, so I would need the one that passed the check, to come up first.
– The Unknown Dev
Sep 16 at 21:29
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What does multicore assembly language look like?
...on, but it's an answer to a question that appears in the comments. Essentially, the question is what support the hardware gives to multi-threaded operation.
Nicholas Flynt had it right, at least regarding x86. In a multi threaded environment (Hyper-threading, multi-core or multi-processor), the B...
SQL SELECT WHERE field contains words
...%'
OR column1 LIKE '%word2%'
OR column1 LIKE '%word3%'
If you need all words to be present, use this:
SELECT * FROM mytable
WHERE column1 LIKE '%word1%'
AND column1 LIKE '%word2%'
AND column1 LIKE '%word3%'
If you want something faster, you need to look into full text search, and this...
Remove everything after a certain character
... to remove everything after a certain character or just choose everything up to that character? I'm getting the value from an href and up to the "?", and it's always going to be a different amount of characters.
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Graph visualization library in JavaScript
...ructure that represents a directed graph, and I want to render that dynamically on an HTML page. These graphs will usually be just a few nodes, maybe ten at the very upper end, so my guess is that performance isn't going to be a big deal. Ideally, I'd like to be able to hook it in with jQuery so th...
How to create module-wide variables in Python? [duplicate]
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Here is what is going on.
First, the only global variables Python really has are module-scoped variables. You cannot make a variable that is truly global; all you can do is make a variable in a particular scope. (If you make a variable inside the Python interpreter, and then import other mo...
Mongoose.js: Find user by username LIKE value
...ke to to go find a user in mongoDb by looking for a user called value.
The problem with:
13 Answers
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How do exceptions work (behind the scenes) in c++
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Instead of guessing, I decided to actually look at the generated code with a small piece of C++ code and a somewhat old Linux install.
class MyException
{
public:
MyException() { }
~MyException() { }
};
void my_throwing_function(bool throwit)
{
if (...
How can I extract all values from a dictionary in Python?
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If you want all of the values, use this:
dict_name_goes_here.values()
If you want all of the keys, use this:
dict_name_goes_here.keys()
IF you want all of the items (both keys and values), I would use this:
dict_name_goes_here.ite...