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Compare two DataFrames and output their differences side-by-side
...original question
The first step is to concatenate the DataFrames horizontally with the concat function and distinguish each frame with the keys parameter:
df_all = pd.concat([df.set_index('id'), df2.set_index('id')],
axis='columns', keys=['First', 'Second'])
df_all
It's pr...
Get element inside element by class and ID - JavaScript
...er than worrying about browser compatibility yourself (let someone else do all the work). If you want just a library to do that, then Sizzle will work great. In Sizzle, this would be be done like this:
Sizzle("#foo .bar")[0].innerHTML = "Goodbye world!";
jQuery has the Sizzle library built-in...
ipython reads wrong python version
I've been having trouble with Python, iPython and the libraries. The following points show the chain of the problematics. I'm running Python 2.7 on Mac Lion.
...
Understanding CUDA grid dimensions, block dimensions and threads organization (simple explanation) [
... threads each: then at a given moment no more than 4*768 threads will be really running in parallel (if you planned more threads, they will be waiting their turn).
Software
threads are organized in blocks. A block is executed by a multiprocessing unit.
The threads of a block can be indentified (in...
Extracting just Month and Year separately from Pandas Datetime column
...
what actually does pd.Datetimeindex do?
– JOHN
Apr 16 '18 at 5:24
1
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Difference between exit() and sys.exit() in Python
In Python, there are two similarly-named functions, exit() and sys.exit() . What's the difference and when should I use one over the other?
...
What is the meaning of “… …” token? i.e. double ellipsis operator on parameter pack
...mma is purely optional; §8.3.5/4 does say
Where syntactically correct and where “...” is not part of an abstract-declarator, “, ...” is synonymous with “...”.
This is within an abstract-declarator, [edit] but Johannes makes a good point that they are referring to an abstract-decla...
How to get the original value of an attribute in Rails
...ibute will give you the previous value.
For rails 5.1+
Copied from Lucas Andrade's answer below: https://stackoverflow.com/a/50973808/9359123
Appending _was is deprecated in rails 5.1, now you should append _before_last_save
Something like:
before_save object
do_something_with object.name_...
Make the current commit the only (initial) commit in a Git repository?
...e using submodules, you should use e.g. interactive rebase
Step 1: remove all history (Make sure you have backup, this cannot be reverted)
cat .git/config # note <github-uri>
rm -rf .git
Step 2: reconstruct the Git repo with only the current content
git init
git add .
git commit -m "Init...
How to set Oracle's Java as the default Java in Ubuntu?
...of the JVM, you don't need to update your .bashrc file, it should automatically point to the new version.
If you want to set JAVA_HOME environment variables globally and at system level means use should set in /etc/environment file.
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