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Rake just one migration
I'm trying to run just one migration out of a whole bunch in my rails app. How can I do this? I don't want to run any of the migrations before or after it. Thanks.
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Remove all values within one list from another list? [duplicate]
...s surprised by results, so I want to share it with you.
Experiments were done using pythonbenchmark tool and with
a = range(1,50000) # Source list
b = range(1,15000) # Items to remove
Results:
def comprehension(a, b):
return [x for x in a if x not in b]
5 tries, average time 12.8 sec
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iPhone app signing: A valid signing identity matching this profile could not be found in your keycha
I'm pulling my hair out over this. I just downloaded the iPhone 3.0 SDK , but now I can't get my provisioning profiles to work. Here is what I have tried:
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How to test if parameters exist in rails
...ets triggered. How can I make this part ONLY get triggered if both params[:one] and params[:two] is set?
14 Answers
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Different ways of clearing lists
Is there any reason to do anything more complicated than one of these two lines when you want to clear a list in Python?
8 ...
How to check if a value exists in a dictionary (python)
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>>> d = {'1': 'one', '3': 'three', '2': 'two', '5': 'five', '4': 'four'}
>>> 'one' in d.values()
True
Out of curiosity, some comparative timing:
>>> T(lambda : 'one' in d.itervalues()).repeat()
[0.28107285499572754, 0.2...
FFmpeg: How to split video efficiently?
....ts -vcodec copy -acodec copy -ss 00:30:00 -t 01:00:00 -sn test2.mkv
echo "One command"
time ffmpeg -v quiet -y -i input.ts -vcodec copy -acodec copy -ss 00:00:00 -t 00:30:00 \
-sn test3.mkv -vcodec copy -acodec copy -ss 00:30:00 -t 01:00:00 -sn test4.mkv
Which outputs...
Two commands
real 0m...
Working with $scope.$emit and $scope.$on
How can I send my $scope object from one controller to another using .$emit and .$on methods?
12 Answers
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How to filter a dictionary according to an arbitrary condition function?
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@Datanovice I'm sure one could. One could also open a new question with sufficient detail to get a more useful answer ;)
– Thomas
May 2 '18 at 14:09
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How many double numbers are there between 0.0 and 1.0?
...ve a 52-bit fraction; between any two adjacent powers of two (inclusive of one and exclusive of the next one), there will therefore be 2 to the 52th power different doubles (i.e., 4503599627370496 of them). For example, that's the number of distinct doubles between 0.5 included and 1.0 excluded, an...