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Immutable vs Mutable types
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What? Floats are immutable? But can't I do
x = 5.0
x += 7.0
print x # 12.0
Doesn't that "mut" x?
Well you agree strings are immutable right? But you can do the same thing.
s = 'foo'
s += 'bar'
print s # foobar
The value of the variable changes, but it changes by chang...
Javascript fuzzy search that makes sense
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10 Answers
10
Active
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What is an intuitive explanation of the Expectation Maximization technique? [closed]
... parameters:
import numpy as np
from scipy import stats
np.random.seed(110) # for reproducible results
# set parameters
red_mean = 3
red_std = 0.8
blue_mean = 7
blue_std = 2
# draw 20 samples from normal distributions with red/blue parameters
red = np.random.normal(red_mean, red_std, size=20)
b...
Relative frequencies / proportions with dplyr
...n = n()) %>%
mutate(freq = n / sum(n))
# am gear n freq
# 1 0 3 15 0.7894737
# 2 0 4 4 0.2105263
# 3 1 4 8 0.6153846
# 4 1 5 5 0.3846154
From the dplyr vignette:
When you group by multiple variables, each summary peels off one level of the grouping. That makes ...
Adding gif image in an ImageView in android
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80
First, copy your GIF image into Asset Folder of your app
create following classes and paste the ...
Creating range in JavaScript - strange syntax
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+1000
Understanding this "hack" requires understanding several things:
Why we don't just do Array(5).map(...)
How Function.prototype.app...
Build an ASCII chart of the most commonly used words in a given text [closed]
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LabVIEW 51 nodes, 5 structures, 10 diagrams
Teaching the elephant to tap-dance is never pretty. I'll, ah, skip the character count.
The program flows from left to right:
sha...
How do I set the rounded corner radius of a color drawable using xml?
... a white background, black border and rounded corners:
<?xml version="1.0" encoding="UTF-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
<solid android:color="#ffffffff"/>
<stroke android:width="3dp"
android:color="...
Selecting with complex criteria from pandas.DataFrame
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406
Sure! Setup:
>>> import pandas as pd
>>> from random import randint
>&gt...
Getting a map() to return a list in Python 3.x
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802
Do this:
list(map(chr,[66,53,0,94]))
In Python 3+, many processes that iterate over iterable...