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foldl versus foldr behavior with infinite lists
...r folding a list of n values [x1, x2, x3, x4 ... xn ] with some function f and seed z.
foldl is:
Left associative: f ( ... (f (f (f (f z x1) x2) x3) x4) ...) xn
Tail recursive: It iterates through the list, producing the value afterwards
Lazy: Nothing is evaluated until the result is needed
Backw...
Why is there a `null` value in JavaScript?
...pt, there are two values which basically say 'I don't exist' - undefined and null .
12 Answers
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How do I calculate percentiles with python/numpy?
...ed in the SciPy Stats package. It has the percentile function you're after and many other statistical goodies.
percentile() is available in numpy too.
import numpy as np
a = np.array([1,2,3,4,5])
p = np.percentile(a, 50) # return 50th percentile, e.g median.
print p
3.0
This ticket leads me to b...
What is the difference between persist() and merge() in JPA and Hibernate?
What is the difference between persist() and merge() in Hibernate?
4 Answers
4
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Django 1.7 - makemigrations not detecting changes
...ion does not make it obvious that you need to add the app label to the command, as the first thing it tells you to do is python manage.py makemigrations which will fail. The initial migration is done when you create your app in version 1.7, but if you came from 1.6 it wouldn't have been carried out....
ImportError: No module named site on Windows
... does not include source) . I then ran the installer, selected 'All Users' and all was fine. I installed Python into the default location:
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Difference between View and table in sql
What is the main difference between view and table in SQL. Is there any advantage of using views instead of tables.
7 Answe...
Why would I make() or new()?
...ents dedicate many paragraphs to explaining the difference between new() and make() , but in practice, you can create objects within local scope and return them.
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How to use Python's pip to download and keep the zipped files for a package?
If I want to use the pip command to download a package (and its dependencies), but keep all of the zipped files that get downloaded (say, django-socialregistration.tar.gz) - is there a way to do that?
...
ld cannot find an existing library
...too. This way, you can have several versions of a library in your system, and if an application needs a specific one, it can link to it, while in general, the newest one is chosen by symlink. I do not know why this symlink was missing.
– Svante
Dec 3 '08 at 1...