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Group by multiple columns in dplyr, using string vector input
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data = data.frame(
asihckhdoydkhxiydfgfTgdsx = sample(LETTERS[1:3], 100, replace=TRUE),
a30mvxigxkghc5cdsvxvyv0ja = sample(LETTERS[1:3], 100, replace=TRUE),
value = rnorm(100)
)
# get the columns we want to average within
columns = names(data)[-3]
library(dplyr)
df1 <- data %>%...
Example of Named Pipes
...tring[] args)
{
StartServer();
Task.Delay(1000).Wait();
//Client
var client = new NamedPipeClientStream("PipesOfPiece");
client.Connect();
StreamReader reader = new StreamReader(client);
StreamWriter writer...
How to make blinking/flashing text with CSS 3
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10 Answers
10
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Two statements next to curly brace in an equation
...cument}
\begin{equation}
f(x)=\begin{cases}
1, & \text{if $x<0$}.\\
0, & \text{otherwise}.
\end{cases}
\end{equation}
\end{document}
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improve this answer
...
surface plots in matplotlib
...t.figure()
ax = fig.add_subplot(111, projection='3d')
x = y = np.arange(-3.0, 3.0, 0.05)
X, Y = np.meshgrid(x, y)
zs = np.array(fun(np.ravel(X), np.ravel(Y)))
Z = zs.reshape(X.shape)
ax.plot_surface(X, Y, Z)
ax.set_xlabel('X Label')
ax.set_ylabel('Y Label')
ax.set_zlabel('Z Label')
plt.show()
...
Is there anyway to exclude artifacts inherited from a parent POM?
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Ahmed Ashour
4,1291010 gold badges2828 silver badges4646 bronze badges
answered Apr 21 '10 at 15:28
Pascal ThiventPascal...
What is “entropy and information gain”?
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1051
I assume entropy was mentioned in the context of building decision trees.
To illustrate, imag...
What is sr-only in Bootstrap 3?
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.sr-only {
position: absolute;
width: 1px;
height: 1px;
padding: 0;
margin: -1px;
overflow: hidden;
clip: rect(0,0,0,0);
border: 0;
}
Is it important or can I remove it? Works fine without.
It's important, don't remove it.
You should always consider screen readers for acces...
What is the difference between BIT and TINYINT in MySQL?
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answered Nov 14 '08 at 14:39
Robert GambleRobert Gamble
94.3k2121 gold badges139139 silver badges135135 bronze badges
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