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Hidden features of Perl?
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One of my favourite features in Perl is using the boolean || operator to select between a set of choices.
$x = $a || $b;
# $x = $a, if $a is true.
# $x = $b, otherwise
This means one can write:
$x = $a || $b || $c || 0;
to take the first true value from $a, $b, and $c, or a default of 0...
How to deal with SettingWithCopyWarning in Pandas?
...owing, which does not always work as expected, particularly when the first selection returns a copy. [see GH5390 and GH5597 for background discussion.]
df[df['A'] > 2]['B'] = new_val # new_val not set in df
The warning offers a suggestion to rewrite as follows:
df.loc[df['A'] > 2, 'B'] =...
Oracle 分组后取每组第一条数据 - 数据库(内核) - 清泛网 - 专注C/C++及内核技术
...据Oracle 分组后取每组第一条数据的SQL如下，亲测有效：SELECT * FROM (SELECT ROW_NUMBER() OVER(PARTITION BY T field1, T Oracle 分组后取每组第一条数据的SQL如下，亲测有效：
SELECT *
FROM (SELECT ROW_NUMBER() OVER(PARTITION BY T.field1, T.field2 ORDER...
Apple Mach-O Linker Error when compiling for device
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In some case error log window displaying .xctest error, to fix it
-> Select your project
-> Beside this(just before General tab) select your projectTest file from dropdown
-> There is one option (like ProjNameTests)
-> In Host Application, select your project from dropdown only if ...
How do I reformat HTML code using Sublime Text 2?
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You don't need any plugins to do this.
Just select all lines (Ctrl A) and then from the menu select Edit → Line → Reindent.
This will work if your file is saved with an extension that contains HTML like .html or .php.
If you do this often, you may find this key ma...
jQuery OR Selector?
I am wondering if there is a way to have "OR" logic in jQuery selectors. For example, I know an element is either a descendant of an element with class classA or classB, and I want to do something like elem.parents('.classA or .classB') . Does jQuery provide such functionality?
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How to get a list of all files that changed between two Git commits?
...om the git diff documentation:
diff-filter=[(A|C|D|M|R|T|U|X|B)…[*]]
Select only files that are Added (A), Copied (C), Deleted (D), Modified (M), Renamed (R), have their type (i.e. regular file, symlink, submodule, …) changed (T), are Unmerged (U), are Unknown (X), or have had their pairi...
Best way to get identity of inserted row?
...rator error', GETDATE());
--Display the result set of the table variable.
SELECT NewScrapReasonID, Name, ModifiedDate FROM @MyTableVar;
--Display the result set of the table.
SELECT ScrapReasonID, Name, ModifiedDate
FROM Production.ScrapReason;
GO
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Android add placeholder text to EditText
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In Android Studio you can add Hint (Place holder) through GUI. First select EditText field on designer view. Then Click on Component Tree Left side of IDE (Normally it's there, but it may be there minimized) There you can see Properties of selected EditText. Find Hint field as below Image
T...
How can I set the PHP version in PHPStorm?
...ndows:
File -> Settings -> Languages & Frameworks > PHP
then select your PHP version, for example, 7.0
This is very useful when your local system runs PHP 7.0, for example, but production is running PHP 5.5.
That way PhpStorm will warn you which parts will not work in production, show ...