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What is the difference between join and merge in Pandas?
Suppose I have two DataFrames like so:
7 Answers
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PostgreSQL function for last inserted ID
...typically but not necessarily used as default values for surrogate primary keys, with the SERIAL pseudo-type).
If you are interested in getting the id of a newly inserted row, there are several ways:
Option 1: CURRVAL(<sequence name>);.
For example:
INSERT INTO persons (lastname,fir...
What is an OS kernel ? How does it differ from an operating system? [closed]
I am not able to understand the difference between a kernel and an operating system. I do not see any difference between them. Is the kernel an operating system?
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Building big, immutable objects without using constructors having long parameter lists
... you want both an easier to read and immutable object once created?
I think a fluent interface CORRECTLY DONE would help you.
It would look like this (purely made up example):
final Foo immutable = FooFactory.create()
.whereRangeConstraintsAre(100,300)
.withColor(Color.BLUE)
.withArea...
Omitting the first line from any Linux command output
I have a requirement where i'd like to omit the 1st line from the output of ls -latr "some path" Since I need to remove total 136 from the below output
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How to have conditional elements and keep DRY with Facebook React's JSX?
...ited Apr 15 '15 at 20:15
Michal Kordas
8,66566 gold badges3737 silver badges7676 bronze badges
answered Mar 20 '14 at 16:21
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jQuery's jquery-1.10.2.min.map is triggering a 404 (Not Found)
....map or jquery-2.0.3.min.map, but can happen with anything) first thing to know is this is only requested when using the DevTools.
Your users will not be hitting this 404.
Now you can fix this or disable the sourcemap functionality.
Fix: get the files
Next, it's an easy fix. Head to http://jque...
pandas three-way joining multiple dataframes on columns
...on. If I have more than a handful of dataframes, I'd put them in a list like this (generated via list comprehensions or loops or whatnot):
dfs = [df0, df1, df2, dfN]
Assuming they have some common column, like name in your example, I'd do the following:
df_final = reduce(lambda left,right: pd.m...
What's the difference between dynamic (C# 4) and var?
I had read a ton of articles about that new keyword that is shipping with C# v4, but I couldn't make out the difference between a "dynamic" and "var".
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How to merge the current branch into another branch
I have two branches, master and dev. I always work on dev and only check code into the master branch once it's been approved for production use. When I do so, I have to do the following:
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