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Determine the type of an object?
...object, and isinstance() to check an object’s type against something. Usually, you want to use isistance() most of the times since it is very robust and also supports type inheritance.
To get the actual type of an object, you use the built-in type() function. Passing an object as the only param...
Using global variables between files?
...e project, with around 50 files, and I need to define global variables for all those files.
6 Answers
...
How do I get the row count of a pandas DataFrame?
...[0].count()", "len(data.index)"],
xlabel="data rows"
)
EDIT: As @Dan Allen noted in the comments len(df.index) and df[0].count() are not interchangeable as count excludes NaNs,
share
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How to re import an updated package while in Python Interpreter? [duplicate]
.... When targeting 3 or later, either reference the appropriate module when calling reload or import it.
Takeaway:
Python3 >= 3.4: importlib.reload(packagename)
Python3 < 3.4: imp.reload(packagename)
Python2: continue below
Use the reload builtin function:
https://docs.python.org/2/libr...
Peak-finding algorithm for Python/SciPy
...ant to understand well its parameters width, threshold, distance and above all prominence to get a good peak extraction.
According to my tests and the documentation, the concept of prominence is "the useful concept" to keep the good peaks, and discard the noisy peaks.
What is (topographic) promine...
Rails 4 multiple image or file upload using carrierwave
...tiple_image_upload_carrierwave
In gem file
gem 'carrierwave'
bundle install
rails generate uploader Avatar
Create post scaffold
rails generate scaffold post title:string
Create post_attachment scaffold
rails generate scaffold post_attachment post_id:integer avatar:string
rake db:migrate
...
Bash continuation lines
... like a single string which crosses lines, while indenting but not getting all those spaces, one approach you can try is to ditch the continuation line and use variables:
$ a="continuation"
$ b="lines"
$ echo $a$b
continuationlines
This will allow you to have cleanly indented code at the expense ...
Event system in Python
...r methods', which is a
simple implementation of the Observer pattern.
Basically, the handler methods (callables) are stored in an array and are each called when the event 'fires'.
Publish-Subscribe
The disadvantage of Observer event systems is that you can only register the handlers on the actual Ev...
What does `:_*` (colon underscore star) do in Scala?
...tes: MetaData, scope: NamespaceBinding,
child: Node*)
which is called as
new Elem(prefix, label, attributes, scope,
child1, child2, ... childN)
but here there is only a sequence, not child1, child2, etc. so this allows the result sequence to be used as the input to the constru...
Reading a huge .csv file
...
You are reading all rows into a list, then processing that list. Don't do that.
Process your rows as you produce them. If you need to filter the data first, use a generator function:
import csv
def getstuff(filename, criterion):
with ...
