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Python 3: UnboundLocalError: local variable referenced before assignment [duplicate]
...ather than relying on Globals
def function(Var1, Var2):
if Var2 == 0 and Var1 > 0:
print("Result One")
elif Var2 == 1 and Var1 > 0:
print("Result Two")
elif Var1 < 1:
print("Result Three")
return Var1 - 1
function(1, 1)
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How to change column datatype in SQL database without losing data
I have SQL Server database and I just realized that I can change the type of one of the columns from int to bool .
11 A...
How do I create and read a value from cookie?
How can I create and read a value from a cookie in JavaScript?
19 Answers
19
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How do I get the number of days between two dates in JavaScript?
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Here is a quick and dirty implementation of datediff, as a proof of concept to solve the problem as presented in the question. It relies on the fact that you can get the elapsed milliseconds between two dates by subtracting them, which coerc...
Red black tree over avl tree
AVL and Red black trees are both self-balancing except Red and black color in the nodes. What's the main reason for choosing Red black trees instead of AVL trees? What are the applications of Red black trees?
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LINQ Aggregate algorithm explained
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The easiest-to-understand definition of Aggregate is that it performs an operation on each element of the list taking into account the operations that have gone before. That is to say it performs the action on the first and second element and carr...
Finding three elements in an array whose sum is closest to a given number
Given an array of integers, A 1 , A 2 , ..., A n , including negatives and positives, and another integer S. Now we need to find three different integers in the array, whose sum is closest to the given integer S. If there exists more than one solution, any of them is ok.
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Finding duplicate values in MySQL
I have a table with a varchar column, and I would like to find all the records that have duplicate values in this column. What is the best query I can use to find the duplicates?
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How do I convert seconds to hours, minutes and seconds?
...his is the best way, IMHO, as you can then use arithmetic on the timedelta and any datetime objects.
– Matthew Schinckel
Apr 22 '09 at 3:13
13
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data.table vs dplyr: can one do something well the other can't or does poorly?
...able , not so much with dplyr . I've read through some dplyr vignettes and examples that have popped up on SO, and so far my conclusions are that:
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