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Add column with constant value to pandas dataframe [duplicate]
...ere's how DataFrame.align() works with partially aligned indices:
In [7]: from pandas import DataFrame
In [8]: from numpy.random import randint
In [9]: df = DataFrame({'a': randint(3, size=10)})
In [10]:
In [10]: df
Out[10]:
a
0 0
1 2
2 0
3 1
4 0
5 0
6 0
7 0
8 0
9 0
In [11]: s = d...
Python Progress Bar
... a progress meter to your loops in a second:
In [1]: import time
In [2]: from tqdm import tqdm
In [3]: for i in tqdm(range(10)):
....: time.sleep(3)
60%|██████ | 6/10 [00:18<00:12, 0.33 it/s]
Also, there is a graphical version of tqdm since v2.0.0 (d977a0c):
In [1]:...
How to play with Control.Monad.Writer in haskell?
...t has logging capabilities, but also does something else - say it can read from an environment too. You'd implement this as
type RW r w a = ReaderT r (Writer w a)
Now because the writer is inside the ReaderT monad transformer, if you want to log output you can't use tell w (because that only oper...
Number of elements in a javascript object
Is there a way to get (from somewhere) the number of elements in a javascript object?? (i.e. constant-time complexity).
6 A...
How to get the return value from a thread in python?
...eturns a string 'foo' . How can I get the value 'foo' which is returned from the thread's target?
20 Answers
...
(![]+[])[+[]]… Explain why this works
...
Where does the "i" come from?
– Josh Stodola
Nov 13 '10 at 5:00
5
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How to load/edit/run/save text files (.py) into an IPython notebook cell?
...
EDIT: Starting from IPython 3 (now Jupyter project), the notebook has a text editor that can be used as a more convenient alternative to
load/edit/save text files.
A text file can be loaded in a notebook cell with the magic command %loa...
Managing relationships in Laravel, adhering to the repository pattern
...s (or any other use case). Our "implementation" is built around Eloquent.
From a practical point of view, this makes sense. We're unlikely to change data sources to something Eloquent can't handle (to a non-sql data source).
ORMS
The trickiest part of this setup, for me at least, is determing if ...
prototype based vs. class based inheritance
...
No, sorry, CLOS is from the late 80's dreamsongs.com/CLOS.html Smalltalk from 1980 en.wikipedia.org/wiki/Smalltalk and Simula with full object orientation from 1967-68 en.wikipedia.org/wiki/Simula
– Charlie Martin
...
How to get existing fragments when using FragmentPagerAdapter
...create Fragments for your ViewPager, but upon Activity recreation (whether from a device rotation or the system killing your App to regain memory) these Fragments won't be created again, but instead their instances retrieved from the FragmentManager. Now say your Activity needs to get a reference to...