# Testar Syntax Highlighter

$A=\begin{bmatrix} \frac{1}{3} & \frac{1}{3} & \frac{1}{3} \[6pt] \frac{2}{3} &\frac{-1}{3} &\frac{-1}{3} \[6pt] \frac{1}{3} & \frac{1}{3} & \frac{-2}{3} \end{bmatrix}$

$n=\underbrace{1+1+\cdots+1}_{\text{n times}}.$

## Test för R

plotSubset <- data.frame(scale(mdrrDescr[, c("nC", "X4v")]))
xyplot(nC ~ X4v,
data = plotSubset,
groups = mdrrClass,
auto.key = list(columns = 2))


## Test för Python

from sklearn.feature_selection import VarianceThreshold
X = [[0, 0, 1], [0, 1, 0], [1, 0, 0], [0, 1, 1], [0, 1, 0], [0, 1, 1]]
sel = VarianceThreshold(threshold=(.8 * (1 - .8)))
sel.fit_transform(X)
array([[0, 1],
[1, 0],
[0, 0],
[1, 1],
[1, 0],
[1, 1]])


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