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Get the first element of each tuple in a list in Python [duplicate]
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Use a list comprehension:
res_list = [x[0] for x in rows]
Below is a demonstration:
>>> rows = [(1, 2), (3, 4), (5, 6)]
>>> [x[0] for x in rows]
[1, 3, 5]
>>>
Alternately, you could use unpacking instead of x[0]:
res_li...
What's the difference between ES6 Map and WeakMap?
...e: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakMap):
Keys of WeakMaps are of the type Object only. Primitive data types as
keys are not allowed (e.g. a Symbol can't be a WeakMap key).
Nor can a string, number, or boolean be used as a WeakMap key. A M...
not None test in Python [duplicate]
...r of the latter two, since val could potentially be of a type that defines __eq__() to return true when passed None.
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How do I find where JDK is installed on my windows machine?
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Actually, the form %VAR_NAME% is Windows
– sblundy
Jan 13 '11 at 14:29
2
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How do I run a single test with Nose in Pylons
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nosetests appname.tests.functional.test_controller should work, where the file is named test_controller.py.
To run a specific test class and method use a path of the form module.path:ClassNameInFile.method_name, that is, with a colon separating the module/file pa...
What does 'require: false' in Gemfile mean?
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This means install the gem, but do not call require when you start Bundler. So you will need to manually call
require "whenever"
if you want to use the library.
If you were to do
gem "whenever", require: "whereever"
then bundler woul...
What does `someObject.new` do in Java?
... And, as you can tell, this can be incredibly confusing. Ideally, inner classes should be implementation details of the outer class and not be exposed to the outside world.
– Eric Jablow
Mar 30 '13 at 23:45
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Concatenate two slices in Go
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Is this at all performant when the slices are quite big? Or does the compiler not really pass all the elements as parameters?
– Toad
Sep 24 '14 at 8:57
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Python timedelta in years
... year=from_date.year-years)
Your question originally said you wanted to know how many years it's been since some date. Assuming you want an integer number of years, you can guess based on 365.25 days per year and then check using either of the yearsago functions defined a...
glob exclude pattern
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Really interesting solution! But my case is going to be extremely slow to make a read twice. Also if the content of a folder is big on an network directory, is going to be slow again. But in any case, really handy.
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