Fisher's natural breaks classification

The function provides an interface to finding class intervals for continuous numerical variables, for example for choosing colours for plotting maps.

Usage

fisher(vec, n = 7, diglab = 2)

Arguments

vec

a continuous numerical variable

n

number of classes required (n = 7 is default)

diglab

number of digits (n = 2 is default)

Value

Vector with clustering

Details

The "fisher" style uses the algorithm proposed by W. D. Fisher (1958) and discussed by Slocum et al. (2005) as the Fisher-Jenks algorithm. This function is adopted from the classInt package.

References

Bivand, R. (2018). classInt: Choose Univariate Class Intervals. R package version 0.2-3. https://CRAN.R-project.org/package=classInt

Fisher, W. D. 1958 "On grouping for maximum homogeneity", Journal of the American Statistical Association, 53, pp. 789–798. doi: 10.1080/01621459.1958.10501479.

Author

Martin Haringa