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Clearing a string buffer/builder after loop
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Ah, I think sb.setLength(0); is cleaner and more efficient than declaring it inside the loop. Your solution goes against the performance benefit of using StringBuffer...
– Jon
Feb 11 '10 at 5:38
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Mercurial move changes to a new branch
...evisions 1-2 on a named branch, let's say my-feature. Update to revision 0 and create that branch:
$ hg up 0
$ hg branch my-feature
$ hg ci -m "start new branch my-feature"
The history now looks like this:
@ changeset: 3:b5939750b911
| branch: my-feature
| tag: tip
| parent: ...
How to count total lines changed by a specific author in a Git repository?
Is there a command I can invoke which will count the lines changed by a specific author in a Git repository? I know that there must be ways to count the number of commits as Github does this for their Impact graph.
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Why is require_once so bad to use?
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require_once and include_once both require that the system keeps a log of what's already been included/required. Every *_once call means checking that log. So there's definitely some extra work being done there but enough to detriment th...
Understanding scala enumerations
I have to say I don't understand Scala enumeration classes. I can copy-paste the example from documentation, but I have no idea what is going on.
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What is the difference between String.slice and String.substring?
...xactly like substr() in Firefox. This behavior is observed in both Firefox and IE.
If stop is negative: sets stop to: string.length – Math.abs(stop) (original value), except bounded at 0 (thus, Math.max(0, string.length + stop)) as covered in the ECMA specification.
Source: Rudimentary Art of Pr...
Find the max of two or more columns with pandas
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You can get the maximum like this:
>>> import pandas as pd
>>> df = pd.DataFrame({"A": [1,2,3], "B": [-2, 8, 1]})
>>> df
A B
0 1 -2
1 2 8
2 3 1
>>> df[["A", "B"]]
A B
0 1 -2
1 2 8
2 3 1
>>> df[["A", "B"]].max(axis=1)
0...
Python `if x is not None` or `if not x is None`?
...he if not x is None version to be more clear, but Google's style guide and PEP-8 both use if x is not None . Is there any minor performance difference (I'm assuming not), and is there any case where one really doesn't fit (making the other a clear winner for my convention)?*
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cannot find zip-align when publishing app
... received when I tried to publish my app. I'm using the latest revision of Android SDK Tools (23 which was released today) and SDK Platform-tools (20 which was also released today). I got an APK out of it, but if I tried to upload it to Google Play I got an error complaining that it is not zip align...
How to prevent page scrolling when scrolling a DIV element?
I have reviewed and tested the various functions for preventing the body ability to scroll whilst inside a div and have combined a function that should work.
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