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How to make good reproducible pandas examples
...ly to above)
In [3]: iwantthis
Out[3]:
A B
0 1 5
1 4 6
Explain what the numbers come from: the 5 is sum of the B column for the rows where A is 1.
do show the code you've tried:
In [4]: df.groupby('A').sum()
Out[4]:
B
A
1 5
4 6
But say what's incorrect: the A column is in the...
“loop:” in Java code. What is this, and why does it compile?
...rl: http://www.myserver.com/myfile.mp3
downLoad(url);
Would you all know what this code is (apart from awful)?
Solution: two labels, url and http, a comment www.myserver.com/myfile.mp3 and a method call with a parameter that has the same name (url) as the label. Yup, this compiles (if you define ...
What does [].forEach.call() do in JavaScript?
...ke its first argument and replace this inside of the regular function with whatever you passed call, as the first argument (undefined or null will use window in everyday JS, or will be whatever you passed, if in "strict-mode"). The rest of the arguments will be passed to the original function.
[1...
What Makes a Good Unit Test? [closed]
...t most test the features you actually use. Furthermore, when choosing with what to write these tests; I've found the simple straight-forward 'unit' testing frameworks usually fit the bill perfectly.
– Disillusioned
Jan 11 '10 at 8:10
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Should I put #! (shebang) in Python scripts, and what form should it take?
Should I put the shebang in my Python scripts? In what form?
12 Answers
12
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What is the difference between indexOf() and search()?
...
What does it return for "baby/e/lephant".indexOf(m);?
– RamenChef
Sep 5 '16 at 14:45
1
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What is a tracking branch?
...es
Checking out a local branch from a remote branch automatically creates what is called a tracking branch. Tracking branches are local branches that have a direct relationship to a remote branch. If you’re on a tracking branch and type git push, Git automatically knows which server and branch to...
how can I see what ports mongo is listening on from mongo shell?
If I have a mongo instance running, how can I check what port numbers it is listening on from the shell? I thought that db.serverStatus() would do it but I don't see it. I see this
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Could not change executable permissions on the application
...
yes this was reason I managed to work out what I was doing wrong your answer is correct. Thank you!
– Alex McPherson
Sep 24 '12 at 21:37
1
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Differences in boolean operators: & vs && and | vs ||
I know the rules for && and || but what are & and | ? Please explain these to me with an example.
11 Ans...