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Adding a column to a data.frame
... below. I want to add a column that classifies my data according to column 1 ( h_no ) in that way that the first series of h_no 1,2,3,4 is class 1, the second series of h_no (1 to 7) is class 2 etc. such as indicated in the last column.
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Decreasing for loops in Python impossible?
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for n in range(6,0,-1):
print n
# prints [6, 5, 4, 3, 2, 1]
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How to access the ith column of a NumPy multidimensional array?
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>>> test[:,0]
array([1, 3, 5])
Similarly,
>>> test[1,:]
array([3, 4])
lets you access rows. This is covered in Section 1.4 (Indexing) of the NumPy reference. This is quick, at least in my experience. It's certainly much quicker ...
How do Mockito matchers work?
...re also adapters, which have changed across Mockito versions:
For Mockito 1.x, Matchers featured some calls (such as intThat or argThat) are Mockito matchers that directly accept Hamcrest matchers as parameters. ArgumentMatcher<T> extended org.hamcrest.Matcher<T>, which was used in the ...
How do you use String.substringWithRange? (or, how do Ranges work in Swift?)
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What is NODE_ENV and how to use it in Express?
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Pang
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answered Jun 7 '13 at 8:27
Ed HinchliffeEd ...
List comprehension: Returning two (or more) items for each item
...t;> list(chain.from_iterable((f(x), g(x)) for x in range(3)))
[2, 0, 3, 1, 4, 4]
Timings:
from timeit import timeit
f = lambda x: x + 2
g = lambda x: x ** 2
def fg(x):
yield f(x)
yield g(x)
print timeit(stmt='list(chain.from_iterable((f(x), g(x)) for x in range(3)))',
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Bash variable scope
...lank? I expect that XCODE is incremented in the while loop to a value of 1:
7 Answers
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In MySQL queries, why use join instead of where?
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162
Any query involving more than one table requires some form of association to link the results ...
What is the relationship between UIView's setNeedsLayout, layoutIfNeeded and layoutSubviews?
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I'm still trying to figure this out myself, so take this with some skepticism and forgive me i...