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What does [:] mean?
...he type of population. If population is a list, this line will create a shallow copy of the list. For an object of type tuple or a str, it will do nothing (the line will do the same without [:]), and for a (say) NumPy array, it will create a new view to the same data.
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How to get the URL of the current page in C# [duplicate]
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You may at times need to get different values from URL.
Below example shows different ways of extracting different parts of URL
EXAMPLE: (Sample URL)
http://localhost:60527/WebSite1test/Default2.aspx?QueryString1=1&QueryString2=2
CODE
Response.Write("<br/> " + HttpContext.Curren...
What is the MySQL JDBC driver connection string?
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In the sample code the JDBC url has been hardcoded, not searched in any environment variable
– Jaime Hablutzel
Aug 16 '14 at 13:46
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Getting hold of the outer class object from the inner class object
...involves shadowed variables and how they are accessed.
In the following example (from Oracle), the variable x in main() is shadowing Test.x:
class Test {
static int x = 1;
public static void main(String[] args) {
InnerClass innerClassInstance = new InnerClass()
{
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how to check if object already exists in a list
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It depends on the needs of the specific situation. For example, the dictionary approach would be quite good assuming:
The list is relatively stable (not a lot of inserts/deletions, which dictionaries are not optimized for)
The list is quite large (otherwise the overhead of the dic...
Custom numeric format string to always display the sign
Is there any way I can specify a standard or custom numeric format string to always output the sign, be it +ve or -ve (although what it should do for zero, I'm not sure!)
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Create a dictionary with list comprehension
...(key)) for key in keys)
In simple cases you don't need a comprehension at all...
But if you already have iterable(s) of keys and/or values, just call the dict built-in directly:
1) consumed from any iterable yielding pairs of keys/vals
dict(pairs)
2) "zip'ped" from two separate iterables of keys/v...
Ruby Array find_first object?
...nted to return first value where block returns true
[1,2,3,11,34].detect(&:even?) #=> 2
OR
[1,2,3,11,34].detect{|i| i.even?} #=> 2
If you wanted to return all values where block returns true then use select
[1,2,3,11,34].select(&:even?) #=> [2, 34]
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apache redirect from non www to www
...erName www.example.com for your real server configuration. Apache automatically preserves anything after the / when using the Redirect directive, which is a common misconception about why this method won't work (when in fact it does).
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Qt: can't find -lGL error
I just reinstalled QtCreator, created new project ( Qt Application ) an got this after compilation:
8 Answers
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