Documentation

levelcounts

(Not Recommended) Element counts by level of a nominal or ordinal array

The nominal and ordinal array data types are not recommended. To represent ordered and unordered discrete, nonnumeric data, use the Categorical Arrays (MATLAB) data type instead.

Description

C = levelcounts(A) returns counts of the number of elements in the nominal or ordinal array A equal to each possible level in A.

• If A is a vector, then C is a vector containing as many elements as the number of levels in A.

• If A is a matrix, then C is a matrix of column counts.

• If A is an N-dimensional array, then levelcounts operates along the first nonsingleton dimension.

example

C = levelcounts(A,dim) operates along the dimension dim.

Examples

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Create a nominal array from data in a cell array.

colors = nominal({'r','b','g';'g','r','b';'b','r','g'},...
{'blue','green','red'})
colors = 3x3 nominal array
red        blue      green
green      red       blue
blue       red       green

Count the number of observations of each level in each column.

levelcounts(colors)
ans = 3×3

1     1     1
1     0     2
1     2     0

Count the number of observations of each level in each row.

levelcounts(colors,2)
ans = 3×3

1     1     1
1     1     1
1     1     1

Alternatively, you can use summary to display the counts with their labels. The default is to count elements in each column.

summary(colors)
blue       1      1      1
green      1      0      2
red        1      2      0

You can also count elements in each row.

summary(colors,2)
blue      green      red
1          1        1
1          1        1
1          1        1

Input Arguments

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Nominal or ordinal array, specified as a nominal or ordinal array object created with nominal or ordinal.

Dimension along which to count the number of elements in each level, specified as a positive integer value. For example, if the dimension is 1, then levelcounts counts along each column, while if the dimension is 2, then levelcounts counts along each row.

Data Types: double | single