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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...
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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No Persistence provider for EntityManager named
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30 Answers
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Active
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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...
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 <...
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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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).
>>>...
How do I concatenate or merge arrays in Swift?
...arrays with +, building a new array
let c = a + b
print(c) // [1.0, 2.0, 3.0, 4.0, 5.0, 6.0]
or append one array to the other with += (or append):
a += b
// Or:
a.append(contentsOf: b) // Swift 3
a.appendContentsOf(b) // Swift 2
a.extend(b) // Swift 1.2
print(a) // [1.0, 2.0,...
Split (explode) pandas dataframe string entry to separate rows
...ws()]).reset_index()
Out[55]:
index 0
0 a 1
1 b 1
2 c 1
3 d 2
4 e 2
5 f 2
Then you just have to rename the columns
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The difference between bracket [ ] and double bracket [[ ]] for accessing the elements of a list or
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336
The R Language Definition is handy for answering these types of questions:
http://cran.r-pro...