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What is sys.maxint in Python 3?
...a maximum integer, and I've read to use "sys.maxint" . However, in Python 3 when I call it I get:
6 Answers
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Memoization in Haskell?
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f mf 0 = 0
f mf n = max n $ mf (n `div` 2) +
mf (n `div` 3) +
mf (n `div` 4)
You can get an unmemoized f by using fix f
This will let you test that f does what you mean for small values of f by calling, for example: fix f 123 = 144
We could memoize this by def...
How to get row from R data.frame
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130
x[r,]
where r is the row you're interested in. Try this, for example:
#Add your data
x <...
Import error: No module name urllib2
...on:
The urllib2 module has been split across several modules in Python 3 named urllib.request and urllib.error. The 2to3 tool will automatically adapt imports when converting your sources to Python 3.
So you should instead be saying
from urllib.request import urlopen
html = urlopen("http://ww...
How do I use raw_input in Python 3
I am using Python 3.1 and can't get the raw_input to "freeze" the dos pop-up. The book I'm reading is for Python 2.5 and I'm using Python 3.1
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Specifying rails version to use when creating a new application
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edited Sep 20 '11 at 16:23
Paweł Gościcki
7,05755 gold badges5555 silver badges7474 bronze badges
ans...
Getting SyntaxError for print with keyword argument end=' '
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Are you sure you are using Python 3.x? The syntax isn't available in Python 2.x because print is still a statement.
print("foo" % bar, end=" ")
in Python 2.x is identical to
print ("foo" % bar, end=" ")
or
print "foo" % bar, end=" "
i.e. as a call to...
Static variables in member functions
...e of i will remain through out the program. To add an example:
A o1, o2, o3;
o1.foo(); // i = 1
o2.foo(); // i = 2
o3.foo(); // i = 3
o1.foo(); // i = 4
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No Persistence provider for EntityManager named
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30 Answers
30
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Single Line Nested For Loops
...f the list comprehension (here (x,y)):
>>> [(x, y) for x in [1,2,3] for y in [3,1,4] if x != y]
[(1, 3), (1, 4), (2, 3), (2, 1), (2, 4), (3, 1), (3, 4)]
It's exactly the same as this nested for loop (and, as the tutorial says, note how the order of for and if are the same).
>>>...