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How to add a new row to an empty numpy array
...2,3*i+3])
.....: l = np.asarray(l)
.....:
1000 loops, best of 3: 1.18 ms per loop
In [211]: %%timeit
.....: a = np.empty((0,3), int)
.....: for i in xrange(1000):
.....: a = np.append(a, 3*i+np.array([[1,2,3]]), 0)
.....:
100 loops, best of 3: 18.5 ms per loop
In [214]: np....
rails 3 validation on uniqueness on multiple attributes
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Jason Swett
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answered Jul 18 '10 at 15:55
Christian LescuyerChristian Lesc...
How to sort ArrayList in decreasing order?
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edited Oct 29 '18 at 15:30
Lii
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answere...
Convert a row of a data frame to vector
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Ben BolkerBen Bolker
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Linq to SQL how to do “where [column] in (list of values)”
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Jon SkeetJon Skeet
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How to check if element in groovy array/hash/collection/list?
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8 Answers
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Difference between and ?
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answered Dec 10 '08 at 6:59
ChrisChris
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How to add 10 days to current time in Rails
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286
Use
Time.now + 10.days
or even
10.days.from_now
Both definitely work. Are you sure you'r...
Random row selection in Pandas dataframe
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58
Something like this?
import random
def some(x, n):
return x.ix[random.sample(x.index, n)]
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No empty constructor when create a service
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Avinash R
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answered Aug 8 '12 at 7:20
chiukichiuki
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