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Creating dataframe from a dictionary where entries have different lengths
...hon 3.x:
import pandas as pd
import numpy as np
d = dict( A = np.array([1,2]), B = np.array([1,2,3,4]) )
pd.DataFrame(dict([ (k,pd.Series(v)) for k,v in d.items() ]))
Out[7]:
A B
0 1 1
1 2 2
2 NaN 3
3 NaN 4
In Python 2.x:
replace d.items() with d.iteritems().
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What is the ideal data type to use when storing latitude / longitude in a MySQL database?
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21 Answers
21
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How to print to console in pytest?
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226
By default, py.test captures the result of standard out so that it can control how it prints i...
Default function arguments in Rust
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edited Mar 24 '19 at 21:20
answered Jun 5 '14 at 0:06
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Transform DateTime into simple Date in Ruby on Rails
...ew.to_date
NoMethodError: undefined method 'to_date' for #<DateTime: -1/2,0,2299161>
from (irb):1
>> require 'active_support/core_ext'
=> true
>> DateTime.new.to_date
=> Mon, 01 Jan -4712
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CPU Privilege Rings: Why rings 1 and 2 aren't used?
...of the modern protection model) only has a concept of privileged (ring 0,1,2) and unprivileged, the benefit to rings 1 and 2 were diminished greatly.
The intent by Intel in having rings 1 and 2 is for the OS to put device drivers at that level, so they are privileged, but somewhat separated from th...
mongodb group values by multiple fields
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207
TLDR Summary
In modern MongoDB releases you can brute force this with $slice just off the bas...
Write bytes to file
I have a hexadecimal string (e.g 0CFE9E69271557822FE715A8B3E564BE ) and I want to write it to a file as bytes. For example,
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What is the most efficient/elegant way to parse a flat table into a tree?
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462
Now that MySQL 8.0 supports recursive queries, we can say that all popular SQL databases support...
Scala: Nil vs List()
...intln (Nil equals List())
true
scala> System.identityHashCode(Nil)
374527572
scala> System.identityHashCode(List())
374527572
Nil is more idiomatic and can be preferred in most cases.
Questions?
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