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sed or awk: delete n lines following a pattern
How would I mix patterns and numeric ranges in sed (or any similar tool - awk for example)? What I want to do is match certain lines in a file, and delete the next n lines before proceeding, and I want to do that as part of a pipeline.
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How to use range-based for() loop with std::map?
The common example for C++11 range-based for() loops is always something simple like this:
5 Answers
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How to get line count of a large file cheaply in Python?
...very line is counting as 1. >>> [ 1 for line in range(10) ] [1, 1, 1, 1, 1, 1, 1, 1, 1, 1] >>> sum( 1 for line in range(10) ) 10 >>>
– James
Dec 13 '13 at 5:22
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How to get all possible combinations of a list’s elements?
...oop through all lengths "L":
import itertools
stuff = [1, 2, 3]
for L in range(0, len(stuff)+1):
for subset in itertools.combinations(stuff, L):
print(subset)
Or -- if you want to get snazzy (or bend the brain of whoever reads your code after you) -- you can generate the chain of "co...
How to retrieve an element from a set without removing it?
..., ListIndex, PopAdd, RandomSample, SetUnpacking],
{2**i: set(range(2**i)) for i in range(1, 20)},
argument_name='set size',
function_aliases={first: 'First'})
b.plot()
This plot clearly shows that some approaches (RandomSample, SetUnpacking and ListInde...
Remove the legend on a matplotlib figure
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fig = plt.figure()
ax1 = fig.add_subplot(111)
ax2 = ax1.twinx()
ax1.plot(range(10), range(10, 20), label='line 1')
ax2.plot(range(10), range(30, 20, -1), label='line 2')
fig.legend()
fig.legends = []
plt.show()
share
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How to disable UITextField editing but still accept touch?
...method
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
Return NO from this, and any attempt by the user to edit the text will be rejected.
That way you can leave the field enabled but still prevent people pasting text i...
Random number generation in C++11: how to generate, how does it work? [closed]
...(think of this as the classic rand()). Now you want a random number in the range 0, 1, 2, each with equal probability. Your knee-jerk reaction would be to take rand() % 3. But wait, the remainders 0 and 1 occur more often than the remainder 2, so this isn't correct!
This is why we need proper distr...
Why can't I use a list as a dict key in python?
...on).
Some Timings for Example 3
>>> lists_list = [[i] for i in range(1000)]
>>> stupidlists_set = {stupidlist3([i]) for i in range(1000)}
>>> tuples_set = {(i,) for i in range(1000)}
>>> l = [999]
>>> s = stupidlist3([999])
>>> t = (999,)
>...
Flatten nested dictionaries, compressing keys
... this to all key-paths of the tree.
>>> reduce(lambda a,b:(a,b), range(5))
((((0, 1), 2), 3), 4)
Demonstration (which I'd otherwise put in docstring):
>>> testData = {
'a':1,
'b':2,
'c':{
'aa':11,
'bb':22,
'cc':{
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