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In Scala how do I remove duplicates from a list?
...e part of the file name of interest. Once the map is constructed, you can call the values method to get an Iterable of values--the keys will all be distinct by construction.
– Kipton Barros
Dec 19 '12 at 19:47
...
What is the real overhead of try/catch in C#?
... to make here:
Firstly, there is little or NO performance penalty in actually having try-catch blocks in your code. This should not be a consideration when trying to avoid having them in your application. The performance hit only comes into play when an exception is thrown.
When an exception is th...
typeof for RegExp
...checked before for (typeof t === 'object') : add either -> && !(_t instanceof RegExp) to this check or if possible perform Cleiton's check first. [tl;dr : it is also typeof object, just important if used in "if/else if" ...]
– sebilasse
Jun 16 '15 at...
What is “entropy and information gain”?
...: female
| | ends-vowel=0: male
length>=7
| length=5: male
basically each node represent a test performed on a single attribute, and we go left or right depending on the result of the test. We keep traversing the tree until we reach a leaf node which contains the class prediction (m or f)...
Pimpl idiom vs Pure virtual class interface
...by "value". Often, doesn't make sense to "copy" instances of the class at all. When it does make sense, a polymorphic "Clone" method is usually more appropriate. Examples: A Socket class, a Database class, a "policy" class, anything that would be a "closure" in a functional language.
Both pImpl ...
process.env.NODE_ENV is undefined
... I don't think I missed anything but whenever I call the process.env.NODE_ENV the only value I get back is undefined. According to my research the default value should be 'development'. How is this value dynamically set and where is it set initially?
...
Launch Bootstrap Modal on page load
I don't know javascript at all. The bootstrap documentation says to
18 Answers
18
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How to get an MD5 checksum in PowerShell
...h = [System.BitConverter]::ToString($md5.ComputeHash([System.IO.File]::ReadAllBytes($someFilePath)))
Starting in PowerShell version 4, this is easy to do for files out of the box with the Get-FileHash cmdlet:
Get-FileHash <filepath> -Algorithm MD5
This is certainly preferable since it a...
What is the difference between HAVING and WHERE in SQL?
...nt(1)
From Address
Where State = 'MA'
Group By City
Gives you a table of all cities in MA and the number of addresses in each city.
This code:
select City, CNT=Count(1)
From Address
Where State = 'MA'
Group By City
Having Count(1)>5
Gives you a table of cities in MA with more than 5 address...
Determine device (iPhone, iPod Touch) with iOS
...
@AnilSivadas: UI_USER_INTERFACE_IDIOM() is safe to use in apps that still support iOS < 3.2: it is a macro in UIDevice.h specifically written to default to UIUserInterfaceIdiomPhone on such older iOS versions.
– mkle...