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Transpose a data frame
I need to transpose a large data frame and so I used:
4 Answers
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How to capitalize the first letter of word in a string using Java?
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If you only want to capitalize the first letter of a string named input and leave the rest alone:
String output = input.substring(0, 1).toUpperCase() + input.substring(1);
Now output will have what you want. Check that your input is at least one character long before using this, otherwise you'...
Rails 3 - can't install pg gem
...g= 'PATH_TO_YOUR_PG_CONFIG'
If you are not sure where your pg_config is, and assuming you are on Linux or Mac, you can run the following command:
which pg_config
Your pg-config can be in different locations depending on how you installed postgres.
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Remove carriage return in Unix
...which may or may not be what you want...).
– Tomasz Gandor
Jul 9 '14 at 10:33
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1. Most unixy to...
Is it a bad practice to use negative margins in Android?
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In 2010, @RomainGuy (core Android engineer) stated that negative margins had unspecified behavior.
In 2011, @RomainGuy stated that you can use negative margins on LinearLayout and RelativeLayout.
In 2016, @RomainGuy stated that they have never been ...
ZSH iterm2 increase number of lines history
...ing to change the number of recallable lines in the terminal - not the command history, the output history.
3 Answers
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Multiple select statements in Single query
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"Operand should contain 1 column(s)" - only if your merged tables differ in columns count. They should match. 1 column per table in this example.
– Zon
Apr 22 '16 at 10:54
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Format Float to n decimal places
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You may also pass the float value, and use:
String.format("%.2f", floatValue);
Documentation
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vim repeat find next character 'x'
...s a word (or more words) containing 'x' in between the word I want to edit and the beginning cursor position.
2 Answers
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Not equal != operator on NULL
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<> is Standard SQL-92; != is its equivalent. Both evaluate for values, which NULL is not -- NULL is a placeholder to say there is the absence of a value.
Which is why you can only use IS NULL/IS NOT NULL as predicates for such situ...