cov: cov

In SparkR: R Front End for 'Apache Spark'

Description

Compute the covariance between two expressions.

Usage

cov(x, ...)

covar_samp(col1, col2)

covar_pop(col1, col2)

## S4 method for signature 'characterOrColumn'
cov(x, col2)

## S4 method for signature 'characterOrColumn,characterOrColumn'
covar_samp(col1, col2)

## S4 method for signature 'characterOrColumn,characterOrColumn'
covar_pop(col1, col2)

## S4 method for signature 'SparkDataFrame'
cov(x, colName1, colName2)

Arguments

x	a Column or a SparkDataFrame.
...	additional argument(s). If x is a Column, a Column should be provided. If x is a SparkDataFrame, two column names should be provided.
col1	the first Column.
col2	the second Column.
colName1	the name of the first column
colName2	the name of the second column

Details

cov: Compute the sample covariance between two expressions.

covar_sample: Alias for cov.

covar_pop: Computes the population covariance between two expressions.

cov: When applied to SparkDataFrame, this calculates the sample covariance of two numerical columns of one SparkDataFrame.

Value

The covariance of the two columns.

Note

cov since 1.6.0

covar_samp since 2.0.0

covar_pop since 2.0.0

cov since 1.6.0

See Also

Other aggregate functions: avg(), column_aggregate_functions, corr(), count(), first(), last()

Other stat functions: approxQuantile(), corr(), crosstab(), freqItems(), sampleBy()

Examples

## Not run: 
df <- createDataFrame(cbind(model = rownames(mtcars), mtcars))
head(select(df, cov(df$mpg, df$hp), cov("mpg", "hp"),
                covar_samp(df$mpg, df$hp), covar_samp("mpg", "hp"),
                covar_pop(df$mpg, df$hp), covar_pop("mpg", "hp")))
## End(Not run)

## Not run: 
cov(df, "mpg", "hp")
cov(df, df$mpg, df$hp)
## End(Not run)

SparkR documentation built on June 3, 2021, 5:05 p.m.