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Python's equivalent of && (logical-and) in an if-statement
... different name in Python.
The logical operators && and || are actually called and and or.
Likewise the logical negation operator ! is called not.
So you could just write:
if len(a) % 2 == 0 and len(b) % 2 == 0:
or even:
if not (len(a) % 2 or len(b) % 2):
Some additional information (...
dropping infinite values from dataframes in pandas?
...select the rows that don't have all infinite or missing values via boolean indexing.
all_inf_or_nan = df.isin([np.inf, -np.inf, np.nan]).all(axis='columns')
df[~all_inf_or_nan]
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Why is “if not someobj:” better than “if someobj == None:” in Python?
...a __nonzero__ special method (as do numeric built-ins, int and float), it calls this method. It must either return a bool value which is then directly used, or an int value that is considered False if equal to zero.
Otherwise, if the object has a __len__ special method (as do container built-ins, li...
Ruby : How to write a gem? [closed]
...pdate the ChangeLog.rdoc file, run rake spec and rake rerdoc, open up html/index.html and double-check for any typos.
rake release
(Optional) submit a link and explanation of your new awesome gem to http://rubyflow.com
Sit back and bask in the glory of your first Gem. :)
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jsonify a SQLAlchemy result set in Flask [duplicate]
...
It seems that you actually haven't executed your query. Try following:
return jsonify(json_list = qryresult.all())
[Edit]: Problem with jsonify is, that usually the objects cannot be jsonified automatically. Even Python's datetime fails ;)
Wha...
Running unittest with typical test directory structure
...on -m unittest test.test_antigravity.GravityTestCase.test_method
Running all tests:
You can also use test discovery which will discover and run all the tests for you, they must be modules or packages named test*.py (can be changed with the -p, --pattern flag):
$ cd new_project
$ python -m unitte...
Get selected text from a drop-down list (select box) using jQuery
...s like whether you put an ID on your control, and if not then based on the index of where they occur in the current level of the tree, etc)
– freefaller
Mar 9 '17 at 14:03
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The object 'DF__*' is dependent on column '*' - Changing int to double
Basically I got a table in my EF database with the following properties:
8 Answers
8
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How to implement “select all” check box in HTML?
.../script>
<input type="checkbox" onClick="toggle(this)" /> Toggle All<br/>
<input type="checkbox" name="foo" value="bar1"> Bar 1<br/>
<input type="checkbox" name="foo" value="bar2"> Bar 2<br/>
<input type="checkbox" name="foo" value="bar3"> Bar 3<br/&...
Can modules have properties the same way that objects can?
...s? When I put this code in one file x.py and import it from another, then calling x.y results in AttributeError: 'NoneType' object has no attribute 'c', since _M somehow has value None...
– Stephan202
May 19 '09 at 1:35
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