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Use of “global” keyword in Python
...l variables is seldom considered a good solution.
def bob():
me = "locally defined" # Defined only in local context
print(me)
bob()
print(me) # Asking for a global variable
The above will give you:
locally defined
Traceback (most recent call last):
File "file.py", line 9, in &l...
What does the constant 0.0039215689 represent?
...modern compilers may be smart enough to do this optimization, they are not allowed to do it unless you explicitly tell them to via a compiler flag.
Related: Why doesn't GCC optimize a*a*a*a*a*a to (a*a*a)*(a*a*a)?
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How to supply value to an annotation from a Constant java
... of the form TypeName . Identifier that refer to constant variables.
Actually in java there is no way to protect items in an array. At runtime someone can always do FieldValues.FIELD1[0]="value3", therefore the array cannot be really constant if we look deeper.
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How to find out which view is focused?
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Call getCurrentFocus() on the Activity.
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What is the purpose of a plus symbol before a variable?
this really sounds like a simple question but I had no luck searching. what does the +d in
3 Answers
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Does Typescript support the ?. operator? (And, what's it called?)
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Update: it is supported as of TypeScript 3.7 and called Optional chaining: https://www.typescriptlang.org/docs/handbook/release-notes/typescript-3-7.html#optional-chaining
I can't find any reference to it whatsoever in the TypeScript language specification.
As far as what ...
Where is the “Create Unit Tests” selection?
I have installed the new Visual Studio 2012 Ultimate.
9 Answers
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How to implement a Map with multiple keys? [duplicate]
...ey mk, Object k) and then a Map<MetaKey, Map<Object, V>> internally.
– Jeremy Huiskamp
May 4 '09 at 22:21
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How to calculate the angle between a line and the horizontal axis?
...2(deltaY, deltaX) * 180 / PI
EDIT (Feb. 22, 2017): In general, however, calling atan2(deltaY,deltaX) just to get the proper angle for cos and sin may be inelegant. In those cases, you can often do the following instead:
Treat (deltaX, deltaY) as a vector.
Normalize that vector to a unit vector. ...
ERROR 2006 (HY000): MySQL server has gone away
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max_allowed_packet=64M
Adding this line into my.cnf file solves my problem.
This is useful when the columns have large values, which cause the issues, you can find the explanation here.
On Windows this file is located at: ...