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Booleans, conditional operators and autoboxing
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92
The difference is that the explicit type of the returnsNull() method affects the static typing o...
Generate array of all letters and digits
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answered Jan 31 '11 at 1:26
NakilonNakilon
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What's with 181783497276652981 and 8682522807148012 in Random (Java 7)?
Why were 181783497276652981 and 8682522807148012 chosen in Random.java ?
3 Answers
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How to select rows with one or more nulls from a pandas DataFrame without listing columns explicitly
...p.NaN], range(3), range(3)])
>>> df.isnull()
0 1 2
0 False False False
1 False True False
2 False False True
3 False False False
4 False False False
>>> df.isnull().any(axis=1)
0 False
1 True
2 True
3 False
4 False
dtype: bool
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NumPy array initialization (fill with identical values)
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325
NumPy 1.8 introduced np.full(), which is a more direct method than empty() followed by fill() ...
How to get subarray from array?
I have var ar = [1, 2, 3, 4, 5] and want some function getSubarray(array, fromIndex, toIndex) , that result of call getSubarray(ar, 1, 3) is new array [2, 3, 4] .
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How to check if all elements of a list matches a condition?
I have a list consisting of like 20000 lists. I use each list's 3rd element as a flag. I want to do some operations on this list as long as at least one element's flag is 0, it's like:
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With bash, how can I pipe standard error into another process?
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172
There is also process substitution. Which makes a process substitute for a file.
You can send s...
How to fix the uninitialized constant Rake::DSL problem on Heroku?
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205
Put this in your Rakefile above require 'rake':
require 'rake/dsl_definition'
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python tuple to dict
For the tuple, t = ((1, 'a'),(2, 'b'))
dict(t) returns {1: 'a', 2: 'b'}
6 Answers
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