sample-methods
memisc
0.99.26.3
Take a Sample from a Data Frame-like Object¶
Description¶
The methods below are convenience short-cuts to take samples from data frames and data sets. They result in a data frame or data set, respectively, the rows of which are a sample of the complete data frame/data set.
Usage¶
## S4 method for signature 'data.frame'
sample(x, size, replace = FALSE, prob = NULL)
## S4 method for signature 'data.set'
sample(x, size, replace = FALSE, prob = NULL)
## S4 method for signature 'importer'
sample(x, size, replace = FALSE, prob = NULL)
Arguments¶
x-
a data frame or data set.
size-
an (optional) numerical value, the sample size, defaults to the total number of rows of
x. replace-
a logical value, determines whether sampling takes place with or without replacement.
prob-
a vector of sampling probabities or NULL.
Value¶
A data frame or data set.
Examples¶
for(.i in 1:4)
print(sample(iris,5))
Sepal.Length Sepal.Width Petal.Length Petal.Width Species
89 5.6 3.0 4.1 1.3 versicolor
52 6.4 3.2 4.5 1.5 versicolor
24 5.1 3.3 1.7 0.5 setosa
19 5.7 3.8 1.7 0.3 setosa
90 5.5 2.5 4.0 1.3 versicolor
Sepal.Length Sepal.Width Petal.Length Petal.Width Species
89 5.6 3.0 4.1 1.3 versicolor
109 6.7 2.5 5.8 1.8 virginica
15 5.8 4.0 1.2 0.2 setosa
11 5.4 3.7 1.5 0.2 setosa
4 4.6 3.1 1.5 0.2 setosa
Sepal.Length Sepal.Width Petal.Length Petal.Width Species
108 7.3 2.9 6.3 1.8 virginica
64 6.1 2.9 4.7 1.4 versicolor
139 6.0 3.0 4.8 1.8 virginica
127 6.2 2.8 4.8 1.8 virginica
27 5.0 3.4 1.6 0.4 setosa
Sepal.Length Sepal.Width Petal.Length Petal.Width Species
17 5.4 3.9 1.3 0.4 setosa
35 4.9 3.1 1.5 0.2 setosa
57 6.3 3.3 4.7 1.6 versicolor
88 6.3 2.3 4.4 1.3 versicolor
142 6.9 3.1 5.1 2.3 virginica
