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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
...e .drop argument that does just what you asked for:
df = data.frame(a=rep(1:3,4), b=rep(1:2,6))
df$b = factor(df$b, levels=1:3)
df %>%
group_by(b, .drop=FALSE) %>%
summarise(count_a=length(a))
#> # A tibble: 3 x 2
#> b count_a
#> <fct> <int>
#> 1 1 ...
How to create a UIView bounce animation?
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144
With iOS7 and UIKit Dynamics, there is no longer any need to use CAKeyframeAnimations or UIVie...
Calling a Method From a String With the Method's Name in Ruby
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edited Nov 21 '18 at 21:35
mu is too short
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How to linebreak an svg text within javascript?
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152
This is not something that SVG 1.1 supports. SVG 1.2 does have the textArea element, with auto...
Is it safe to check floating point values for equality to 0?
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115
It is safe to expect that the comparison will return true if and only if the double variable h...
Paging UICollectionView by cells, not screen
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edited May 23 '17 at 12:03
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answered Apr 6 '14 at 15:28
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How to smooth a curve in the right way?
...ort numpy as np
import matplotlib.pyplot as plt
x = np.linspace(0,2*np.pi,100)
y = np.sin(x) + np.random.random(100) * 0.2
yhat = savitzky_golay(y, 51, 3) # window size 51, polynomial order 3
plt.plot(x,y)
plt.plot(x,yhat, color='red')
plt.show()
UPDATE: It has come to my attention that the co...
Maintaining the final state at end of a CSS3 animation
...applied onClick, and, using keyframes, it changes the opacity from 0 to 1 (among other things).
4 Answers
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Replacing NULL with 0 in a SQL server query
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11 Answers
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