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C# LINQ find duplicates in List
... , how can I retrieve a list that contains entries repeated more than once and their values?
9 Answers
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What does -1 mean in numpy reshape?
... (-1,3) but not (-1, -1)). It simply means that it is an unknown dimension and we want numpy to figure it out. And numpy will figure this by looking at the 'length of the array and remaining dimensions' and making sure it satisfies the above mentioned criteria
Now see the example.
z = np.array([[...
@RequestParam vs @PathVariable
What is the difference between @RequestParam and @PathVariable while handling special characters?
7 Answers
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Android Location Providers - GPS or Network Provider?
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There are 3 location providers in Android.
They are:
gps –> (GPS, AGPS): Name of the GPS location provider. This
provider determines location using satellites. Depending on
conditions, this provider may take a while to return a location fi...
How to check for valid email address? [duplicate]
...e sure it is a proper style email address? Been searching since last night and everybody that has answered peoples questions regarding this topic also seems to have problems with it if it is a subdomained email address.
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Are there any reasons to use private properties in C#?
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I use them if I need to cache a value and want to lazy load it.
private string _password;
private string Password
{
get
{
if (_password == null)
{
_password = CallExpensiveOperation();
}
return _password;
...
multiprocessing.Pool: When to use apply, apply_async or map?
...ot seen clear examples with use-cases for Pool.apply , Pool.apply_async and Pool.map . I am mainly using Pool.map ; what are the advantages of others?
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String concatenation vs. string substitution in Python
In Python, the where and when of using string concatenation versus string substitution eludes me. As the string concatenation has seen large boosts in performance, is this (becoming more) a stylistic decision rather than a practical one?
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What is the GAC in .NET?
...le without worrying about conflicts. No more DLL Hell. Each architecture and version gets it's own place to live.
It also gets it own way to browse it in Explorer, so if you go to
C:\Windows\assembly
In windows explorer it lists all the DLLs.
But if you fire up cmd, you can see how it's ...
Postgres: INSERT if does not exist already
...
Postgres 9.5 (released since 2016-01-07) offers an "upsert" command, also known as an ON CONFLICT clause to INSERT:
INSERT ... ON CONFLICT DO NOTHING/UPDATE
It solves many of the subtle problems you can run into when using concurrent operation, which some other answers propose.
...