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how do you filter pandas dataframes by multiple columns
... filter a dataframe (df) by a single column, if we consider data with male and females we might:
6 Answers
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How to Select Every Row Where Column Value is NOT Distinct
... thing that is incorrect with your query is that you are grouping by email and name, that forms a group of each unique set of email and name combined together and hence
aaron and aaron@gmail.com
christy and aaron@gmail.com
john and aaron@gmail.com
are treated as 3 different groups rather all bel...
Difference between single quotes and double quotes in Javascript [duplicate]
I know that in PHP, the only difference between double quotes and single quotes is the interpretation of variable inside a string and the treatment of escape characters.
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xUnit.net: Global setup + teardown?
...y to create one. Just create a base test class that implements IDisposable and do your initialization in the constructor and your teardown in the IDisposable.Dispose method. This would look like this:
public abstract class TestsBase : IDisposable
{
protected TestsBase()
{
// Do "glo...
Bash script error [: !=: unary operator expected
In my script I am trying to error check if the first and only argument is equal to -v but it is an optional argument. I use an if statement but I keep getting the unary operator expected error.
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What is the difference between async.waterfall and async.series
...s://github.com/caolan/async provides 2 similar methods, async.waterfall and async.series .
4 Answers
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How do I parallelize a simple Python loop?
...like concurrent.futures for this, available in Python3 since version 3.2 - and via backport to 2.6 and 2.7 on PyPi.
You can use threads or processes and use the exact same interface.
Multiprocessing
Put this in a file - futuretest.py:
import concurrent.futures
import time, random #...
jQuery returning “parsererror” for ajax request
...
I recently encountered this problem and stumbled upon this question.
I resolved it with a much easier way.
Method One
You can either remove the dataType: 'json' property from the object literal...
Method Two
Or you can do what @Sagiv was saying by returnin...
Where am I wrong about my project and these Javascript Frameworks?
...ization of controls/widgets. ExtJS has a ton of them right out of the box and can always be extended, combined, or munged into whatever monstrosity your business requires.
ExtJS 4 also allows you to "skin" your UI's to further customize the look and feel.
If you are new to JavaScript, and are com...
setTimeout in for-loop does not print consecutive values [duplicate]
... i <= 2; ++i)
doSetTimeout(i);
If you don't do something like this (and there are other variations on this same idea), then each of the timer handler functions will share the same variable "i". When the loop is finished, what's the value of "i"? It's 3! By using an intermediating function,...