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How to use sed to replace only the first occurrence in a file?
...r if you prefer' solution. It would also be good to explain the answers - and to make the answer address the question directly, and then generalize, rather than generalize only. But good answer.
– Jonathan Leffler
Sep 29 '08 at 13:15
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Switch statement: must default be the last case?
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The C99 standard is not explicit about this, but taking all facts together, it is perfectly valid.
A case and default label are equivalent to a goto label. See 6.8.1 Labeled statements. Especially interesting is 6.8.1.4, which enables...
What are C++ functors and their uses?
...about functors in C++. Can someone give me an overview as to what they are and in what cases they would be useful?
14 Answe...
Android Studio Stuck at Gradle Download on create new project
I have installed the new Android Studio . Everything was working fine but when I try to create a new project it gets stuck at downloading Gradle .
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Label encoding across multiple columns in scikit-learn
I'm trying to use scikit-learn's LabelEncoder to encode a pandas DataFrame of string labels. As the dataframe has many (50+) columns, I want to avoid creating a LabelEncoder object for each column; I'd rather just have one big LabelEncoder objects that works across all my columns of data. ...
Confusion between factor levels and factor labels
There seems to be a difference between levels and labels of a factor in R.
Up to now, I always thought that levels were the 'real' name of factor levels, and labels were the names used for output (such as tables and plots). Obviously, this is not the case, as the following example shows:
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Difference between “and” and && in Ruby?
What is the difference between the && and and operators in Ruby?
7 Answers
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Retina displays, high-res background images
...wer, here is the retina detection query I tend to use:
@media
only screen and (-webkit-min-device-pixel-ratio: 2),
only screen and ( min--moz-device-pixel-ratio: 2),
only screen and ( -o-min-device-pixel-ratio: 2/1),
only screen and ( min-device-pixel-ratio: 2),
only screen and ( ...
Getting the last element of a list
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some_list[-1] is the shortest and most Pythonic.
In fact, you can do much more with this syntax. The some_list[-n] syntax gets the nth-to-last element. So some_list[-1] gets the last element, some_list[-2] gets the second to last, etc, all the way down t...
How to enable MySQL Query Log?
...he MySQL function that logs each SQL query statement received from clients and the time that query statement has submitted?
Can I do that in phpmyadmin or NaviCat?
How do I analyse the log?
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