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Why is f(i = -1, i = -1) undefined behavior?
I was reading about order of evaluation violations , and they give an example that puzzles me.
11 Answers
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Prepend a level to a pandas MultiIndex
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A nice way to do this in one line using pandas.concat():
import pandas as pd
pd.concat([df], keys=['Foo'], names=['Firstlevel'])
An even shorter way:
pd.concat({'Foo': df}, names=['Firstlevel'])
This can be generalized to many data frames, see the docs.
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How to load/edit/run/save text files (.py) into an IPython notebook cell?
... individual cells of an open IPython notebook so that they can edited, run and then saved. Can this be done?
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Storing JSON in database vs. having a new column for each key
...ing user related data in my table - I have 2 columns - uid (primary key) and a meta column which stores other data about the user in JSON format.
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What is unit testing? [closed]
...to unit test in a specific language, but no question asking 'what', 'why', and 'when'.
20 Answers
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What is an efficient way to implement a singleton pattern in Java? [closed]
...pt that it is more concise, provides the serialization machinery for free, and provides an ironclad guarantee against multiple instantiation, even in the face of sophisticated serialization or reflection attacks. While this approach has yet to be widely adopted, a single-element enum type is the bes...
Difference between DTO, VO, POJO, JavaBeans?
...JavaBean is a Java Object that is serializable, has a nullary constructor, and allows access to properties using getter and setter methods.
In order to function as a JavaBean class, an object class must obey certain conventions about method naming, construction, and behavior. These conventions ...
How do I install a custom font on an HTML site
I am not using flash or php - and I have been asked to add a custom font to a simple HTML layout. "KG June Bug"
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Count, size, length…too many choices in Ruby?
I can't seem to find a definitive answer on this and I want to make sure I understand this to the "n'th level" :-)
6 Answe...
Appending a vector to a vector [duplicate]
Assuming I have 2 standard vectors:
4 Answers
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