Data table of Distribution

Retrieve or set the data table describing the discrete probability distribution

dTable(x, ...)

# S3 method for Distribution
dTable(x)

# S3 method for Distribution
dTable(x) <- value

# S3 method for Distribution
getData(x, ...)

# S3 method for Distribution
setData(x, value)

Arguments

x

distribution
value

data.table, matrix, data.frame

Value

data.table

Details

A discrete distribution describes the probability of occurrence of each value of a discrete random variable. A discrete random variable is a random variable that has countable values, such as a list of non-negative integers. With a discrete probability distribution, each possible value of the discrete random variable can be associated with a non-zero probability. Thus, a discrete probability distribution is often presented in tabular/matrix form.

In our case, we represent the discrete probability distribution as a matrix (data.table) such that columns represent random variables and rows represent a unique combination of values of respective random variables. The last column is special - it contains a probability or a frequency of respective combination of random variables in the row. This column is denoted as MUDIM.frequency. Columns are named by respective random variables.

When creating a new distribution, the data table does not have to contain a column named MUDIM.frequency. It is created automatically.

Using functions dTable and dTable<- you can read and set the distribution data matrix.

Methods (by class)

  • Distribution: Retrieve probability table

  • Distribution: Set probability table

  • Distribution: Retrieve probability table

  • Distribution: Set probability table

See also

Distribution

Examples

data(Pi)
dTable(Pi)
#>    A B MUDIM.frequency
#> 1: 0 0             0.1
#> 2: 0 1             0.2
#> 3: 1 0             0.3
#> 4: 1 1             0.4

v <- matrix(c(1:10, 1, 1:10, 1),ncol = 2, byrow = FALSE);  #columns of variables
colnames(v) <- c("A","B")

print(v);
#>        A  B
#>  [1,]  1  1
#>  [2,]  2  2
#>  [3,]  3  3
#>  [4,]  4  4
#>  [5,]  5  5
#>  [6,]  6  6
#>  [7,]  7  7
#>  [8,]  8  8
#>  [9,]  9  9
#> [10,] 10 10
#> [11,]  1  1
#        [,1] [,2]
#   [1,]    1    1
#   [2,]    2    2
#   [3,]    3    3
#   [4,]    4    4
#   [5,]    5    5
#   [6,]    6    6
#   [7,]    7    7
#   [8,]    8    8
#   [9,]    9    9
#  [10,]   10   10
#  [10,]    1    1

d <- Distribution("test")
dTable(d) <- v
dTable(d);
#>      A  B MUDIM.frequency
#>  1:  1  1               2
#>  2:  2  2               1
#>  3:  3  3               1
#>  4:  4  4               1
#>  5:  5  5               1
#>  6:  6  6               1
#>  7:  7  7               1
#>  8:  8  8               1
#>  9:  9  9               1
#> 10: 10 10               1