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What is the difference between join and merge in Pandas?
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I always use join on indices:
import pandas as pd
left = pd.DataFrame({'key': ['foo', 'bar'], 'val': [1, 2]}).set_index('key')
right = pd.DataFrame({'key': ['foo', 'bar'], 'val': [4, 5]}).set_index('key')
left.join(right, lsuffix='_l', rsuffix='_r')
val_l ...
What is an undefined reference/unresolved external symbol error and how do I fix it?
...efined reference/unresolved external symbol errors? What are common causes and how to fix/prevent them?
34 Answers
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Depend on a branch or tag using a git URL in a package.json?
Say I've forked a node module with a bugfix and I want to use my fixed version, on a feature branch of course, until the bugfix is merged and released.
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Is there a software-engineering methodology for functional programming? [closed]
...g as it is taught today is entirely focused on object-oriented programming and the 'natural' object-oriented view of the world. There is a detailed methodology that describes how to transform a domain model into a class model with several steps and a lot of (UML) artifacts like use-case-diagrams or ...
Why 0 is true but false is 1 in the shell?
...failure - why it happened, how to fix it, etc. Having zero mean 'success' and non-zero mean failure lets you can check pretty easily for success, and investigate the particular error for more details if you want to. A lot of APIs and frameworks have a similar convention - functions that succeed re...
What is the advantage of using REST instead of non-REST HTTP?
...dy really agrees on what REST is. The wikipedia page is heavy on buzzwords and light on explanation. The discussion page is worth a skim just to see how much people disagree on this. As far as I can tell however, REST means this:
Instead of having randomly named setter and getter URLs and using GET...
Why is null an object and what's the difference between null and undefined?
...n short; undefined is where no notion of the thing exists; it has no type, and it's never been referenced before in that scope; null is where the thing is known to exist, but it's not known what the value is.
One thing to remember is that null is not, conceptually, the same as false or "" or such, e...
Better way to check if a Path is a File or a Directory?
I am processing a TreeView of directories and files. A user can select either a file or a directory and then do something with it. This requires me to have a method which performs different actions based on the user's selection.
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How to check whether a pandas DataFrame is empty?
How to check whether a pandas DataFrame is empty? In my case I want to print some message in terminal if the DataFrame is empty.
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How to decide when to use Node.js?
...out how good Node.js is. Considering how much I love working with jQuery and JavaScript in general, I can't help but wonder how to decide when to use Node.js. The web application I have in mind is something like Bitly - takes some content, archives it.
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