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How do I get the row count of a pandas DataFrame?
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You can use the .shape property or just len(DataFrame.index). However, there are notable performance differences ( len(DataFrame.index) is fastest).
Code to reproduce the plot:
import numpy as np
import pandas as pd
import perfplot
perfplot.save(
"o...
Disable hover effects on mobile browsers
...s of the screen to light up with :hover effects (different background color, etc.) With a tablet, there's no mouse, so I don't want any hover effects.
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vim deleting backward tricks
...urrent backward to beginning of line
dw deletes current to end of current word (including trailing space)
db deletes current to beginning of current word
Read this to learn all the things you can combine with the 'd' command.
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How can a Metro app in Windows 8 communicate with a backend desktop app on the same machine?
...on where you have the UI frontend built using the new Metro style of apps for windows 8, and would like it to communicate with a .NET application running on the desktop on the same local machine (e.g. a windows service app).
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How to access environment variable values?
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Environment variables are accessed through os.environ
import os
print(os.environ['HOME'])
Or you can see a list of all the environment variables using:
os.environ
As sometimes you might need to see a complete list!
# using get will return `None` if a key is not present rather...
How can I fix WebStorm warning “Unresolved function or method” for “require” (Firefox Add-on SDK)
I'm using WebStorm 7 for Firefox Add-on SDK development.
13 Answers
13
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Can I use git diff on untracked files?
... possible to ask git diff to include untracked files in its diff output, or is my best bet to use git add on the newly created files and the existing files I have edited, then use:
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When do you use Java's @Override annotation and why?
What are the best practices for using Java's @Override annotation and why?
27 Answers
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Actual meaning of 'shell=True' in subprocess
...So invoking the shell invokes a program of the user's choosing and is platform-dependent. Generally speaking, avoid invocations via the shell.
Invoking via the shell does allow you to expand environment variables and file globs according to the shell's usual mechanism. On POSIX systems, the shell...
How to choose the right bean scope?
... This is easier to understand if you are familiar with "under the covers" working of a basic servlet web application: How do servlets work? Instantiation, sessions, shared variables and multithreading.
@Request/View/Flow/Session/ApplicationScoped
A @RequestScoped bean lives as long as a single HTTP...