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How to check if an array value exists?
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Is it possible to have an array with identical keys? Wouldn't the second value overwrite the original?
– Citricguy
Jun 9 '12 at 1:51
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Find rows that have the same value on a column in MySQL
...rflow.com/questions/41359879/…
– Syed Asad Abbas Zaidi
Dec 28 '16 at 11:01
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Pandas aggregate count distinct
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How about either of:
>>> df
date duration user_id
0 2013-04-01 30 0001
1 2013-04-01 15 0001
2 2013-04-01 20 0002
3 2013-04-02 15 0002
4 2013-04-02 30 0002
>>> df.groupby("date").agg({"duration": np.sum, "user...
Need to reset git branch to origin version
...e upstream of the current branch.
Since reset is a potentially dangerous call (especially with the --hard option, you will lose any uncommitted changes), it first tells you what it's about to do. For example if you're on branch dev-container with remote called qcpp/dev-container and you enter git ...
Creating a custom JButton in Java
...Looking at the source code you can see that each Die button is drawn dynamically, based on its value.
Here are the basic steps:
Create a class that extends JComponent
Call parent constructor super() in your constructors
Make sure you class implements MouseListener
Put this in the constructor:...
Python Requests - No connection adapters
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You need to include the protocol scheme:
'http://192.168.1.61:8080/api/call'
Without the http:// part, requests has no idea how to connect to the remote server.
Note that the protocol scheme must be all lowercase; if your URL starts with HTTP:// for example, it won’t find the http:// connec...
Drop all the tables, stored procedures, triggers, constraints and all the dependencies in one sql st
...dited Jul 26 '11 at 20:43
Mark Cidade
92k3131 gold badges215215 silver badges229229 bronze badges
answered Sep 24 '09 at 18:18
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File I/O in Every Programming Language [closed]
...lock where you can use the variable f as a stream object returned from the call to open().
When the with block ends, python calls f.close() automatically.
This guarantees the file will be closed when you exit the with block no matter how or when you exit the block
(even if you exit it via an unhan...
How to use git merge --squash?
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Say your bug fix branch is called bugfix and you want to merge it into master:
git checkout master
git merge --squash bugfix
git commit
This will take all the commits from the bugfix branch, squash them into 1 commit, and merge it with your master bra...
How to stop EditText from gaining focus at Activity startup in Android
I have an Activity in Android, with two elements:
52 Answers
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