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Pandas percentage of total with groupby

...swer: # From Paul H import numpy as np import pandas as pd np.random.seed(0) df = pd.DataFrame({'state': ['CA', 'WA', 'CO', 'AZ'] * 3, 'office_id': list(range(1, 7)) * 2, 'sales': [np.random.randint(100000, 999999) for _ in range(12...
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How to convert a boolean array to an int array

... answered Jul 6 '13 at 19:10 BrenBarnBrenBarn 197k2727 gold badges348348 silver badges337337 bronze badges ...
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Difference between '..' (double-dot) and '…' (triple-dot) in range generation?

... | edited Dec 21 '16 at 0:33 answered Mar 13 '12 at 19:48 ...
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How to find all serial devices (ttyS, ttyUSB, ..) on Linux without opening them?

...ystem should contain plenty information for your quest. My system (2.6.32-40-generic #87-Ubuntu) suggests: /sys/class/tty Which gives you descriptions of all TTY devices known to the system. A trimmed down example: # ll /sys/class/tty/ttyUSB* lrwxrwxrwx 1 root root 0 2012-03-28 20:43 /sys/class/...
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How do you plot bar charts in gnuplot?

... Simple bar graph: set boxwidth 0.5 set style fill solid plot "data.dat" using 1:3:xtic(2) with boxes data.dat: 0 label 100 1 label2 450 2 "bar label" 75 If you want to style your bars differently, you can do something like: set style lin...
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How to format numbers by prepending 0 to single-digit numbers?

I want to format a number to have two digits. The problem is caused when 0 – 9 is passed, so I need it to be formatted to 0009 . ...
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Why does GCC generate 15-20% faster code if I optimize for size instead of speed?

I first noticed in 2009 that GCC (at least on my projects and on my machines) have the tendency to generate noticeably faster code if I optimize for size ( -Os ) instead of speed ( -O2 or -O3 ), and I have been wondering ever since why. ...
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How to calculate cumulative normal distribution?

...le: >>> from scipy.stats import norm >>> norm.cdf(1.96) 0.9750021048517795 >>> norm.cdf(-1.96) 0.024997895148220435 In other words, approximately 95% of the standard normal interval lies within two standard deviations, centered on a standard mean of zero. If you need t...
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What is the Ruby (spaceship) operator?

...ther language that supports it. Basically instead of returning 1 (true) or 0 (false) depending on whether the arguments are equal or unequal, the spaceship operator will return 1, 0, or −1 depending on the value of the left argument relative to the right argument. a <=> b := if a < b t...
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Rails I18n validation deprecation warning

I just updated to rails 4.0.2 and I'm getting this warning: 5 Answers 5 ...