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What are the mathematical/computational principles behind this game?
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150
Finite Projective Geometries
The axioms of projective (plane) geometry are slightly different...
How do I convert a float number to a whole number in JavaScript?
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15 Answers
15
Active
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Frequency table for a single variable
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153
Maybe .value_counts()?
>>> import pandas
>>> my_series = pandas.Series([1,2,...
Sample random rows in dataframe
... X2
1 0.7091409 -1.4061361
2 -1.1334614 -0.1973846
3 2.3343391 -0.4385071
4 -0.9040278 -0.6593677
5 0.4180331 -1.2592415
6 0.7572246 -0.5463655
7 -0.8996483 0.4231117
8 -1.0356774 -0.1640883
9 -0.3983045 0.7157506
10 -0.9060305 2.3234110
Then select some rows at random:
> df[s...
Determine the data types of a data frame's columns
...is makes the example exactly reproducible
my.data <- data.frame(y=rnorm(5),
x1=c(1:5),
x2=c(TRUE, TRUE, FALSE, FALSE, FALSE),
X3=letters[1:5])
@Wilmer E Henao H's solution is very streamlined:
sapply(my.data, class)
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How to find the installed pandas version
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375
Check pandas.__version__:
In [76]: import pandas as pd
In [77]: pd.__version__
Out[77]: '0.12....
How to pip install a package with min and max version range?
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edited Jun 15 '16 at 18:32
Leif Arne Storset
66955 silver badges1616 bronze badges
answere...
Reduce, fold or scan (Left/Right)?
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Marc GrueMarc Grue
5,81333 gold badges1313 silver badges1818 bronze badges
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Which is faster in Python: x**.5 or math.sqrt(x)?
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math.sqrt(x) is significantly faster than x**0.5.
import math
N = 1000000
%%timeit
for i in range(N):
z=i**.5
10 loops, best of 3: 156 ms per loop
%%timeit
for i in range(N):
z=math.sqrt(i)
10 loops, best of 3: 91.1 ms per loop
Using Python 3.6.9 ...
Difference between numpy.array shape (R, 1) and (R,)
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554
1. The meaning of shapes in NumPy
You write, "I know literally it's list of numbers and list ...