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Difference between Big-O and Little-O Notation
What is the difference between Big-O notation O(n) and Little-O notation o(n) ?
4 Answers
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Is there a ceiling equivalent of // operator in Python?
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There is no operator which divides with ceil. You need to import math and use math.ceil
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Replace all 0 values to NA
...ays in ?'NULL',
NULL represents the null object in R
which is unique and, I guess, can be seen as the most uninformative and empty object.1 Then it becomes not so surprising that
data.frame(x = c(1, NULL, 2))
# x
# 1 1
# 2 2
That is, R does not reserve any space for this null object.2 Mea...
What is a Y-combinator? [closed]
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@Andre MacFie: I didn't comment on the effort, I commented on the quality. In general, the policy on Stack Overflow is that answers should be self contained, with links to more information.
– Jørgen Fogh...
Use of *args and **kwargs [duplicate]
So I have difficulty with the concept of *args and **kwargs .
11 Answers
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What are the options for storing hierarchical data in a relational database? [closed]
...in this thread suggested. Use an Adjacency List to maintain the hierarchy and use Nested Sets to query the hierarchy.
The problem up until now has been that the coversion method from an Adjacecy List to Nested Sets has been frightfully slow because most people use the extreme RBAR method known as ...
What are the differences between the threading and multiprocessing modules?
I am learning how to use the threading and the multiprocessing modules in Python to run certain operations in parallel and speed up my code.
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Multiple left-hand assignment with JavaScript
...e right most before the left most. so var var1=var2 happens after var3 = 1 and after var2 = var3. it's like var3=1; var2=var3; var var1=var2
– gcb
Jan 29 '13 at 18:51
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How to convert byte array to string and vice versa?
I have to convert a byte array to string in Android, but my byte array contains negative values.
22 Answers
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Mapping two integers to one, in a unique and deterministic way
Imagine two positive integers A and B. I want to combine these two into a single integer C.
18 Answers
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