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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...
How can I get the latest JRE / JDK as a zip file rather than EXE or MSI installer? [closed]
... of JDK from Oracle (for example jdk-7u7-windows-x64.exe)
Download and install 7-Zip (or download 7-Zip portable version if you are not administrator)
With 7-Zip extract all the files from jdk-XuXX-windows-x64.exe into the directory C:\JDK
Execute the following commands in cmd.exe:
cd C:\JDK\.rsrc...
Hashing a dictionary?
...e hash():
hash(frozenset(my_dict.items()))
This is much less computationally intensive than generating the JSON string or representation of the dictionary.
UPDATE: Please see the comments below, why this approach might not produce a stable result.
...
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...
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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improve...
Using global variables between files?
...e project, with around 50 files, and I need to define global variables for all those files.
6 Answers
...
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...
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...
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 ...
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
...