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How to format strings in Java
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140
In addition to String.format, also take a look java.text.MessageFormat. The format less terse a...
dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
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Since dplyr 0.8 group_by gained the .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)...
Paging UICollectionView by cells, not screen
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edited May 23 '17 at 12:03
Community♦
111 silver badge
answered Apr 6 '14 at 15:28
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Is it safe to check floating point values for equality to 0?
...ality between double or decimal type values normally, but I'm wondering if 0 is a special case.
9 Answers
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How to smooth a curve in the right way?
...bove.
import 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 t...
Replacing NULL with 0 in a SQL server query
...ults for the first three columns I get NULL . How can I replace it with 0 ?
11 Answers
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Maintaining the final state at end of a CSS3 animation
I'm running an animation on some elements that are set to opacity: 0; in the CSS. The animation class is applied onClick, and, using keyframes, it changes the opacity from 0 to 1 (among other things).
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Named colors in matplotlib
..._names)
ncols = 4
nrows = n // ncols
fig, ax = plt.subplots(figsize=(12, 10))
# Get height and width
X, Y = fig.get_dpi() * fig.get_size_inches()
h = Y / (nrows + 1)
w = X / ncols
for i, name in enumerate(sorted_names):
row = i % nrows
col = i // nrows
y = Y - (row * h) - h
xi_li...
SSH library for Java [closed]
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answered Jun 15 '09 at 14:27
David RabinowitzDavid Rabinowitz
27.2k1313 gold badges8585 silver badges123123 bronze badges
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Evenly distributing n points on a sphere
...orithm that can give me positions around a sphere for N points (less than 20, probably) that vaguely spreads them out. There's no need for "perfection", but I just need it so none of them are bunched together.
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