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fn_freq {Morefi}

20 May 2024

fn_freq.Rmd

Frequency distribution

Description

The function fn_freq calculates a frequency distribution of data using the functions: cut() and table() from the R base.

Inside the function: The non-cumulative absolute frequency is calculated for each user-defined class interval within the breaks object.

The breaks object must be defined outside the function by the user. For example a sequence of breakpoints of equal distance could be used.

A table with frequencies by class interval is returned.

The function requires defining:

  • df: A vector of data values.
  • breaks: A vector with class intervals.
  • right: Logical, indicating if the intervals should be closed on the right (and open on the left) or vice versa.

Seealso: cut() and table() from the R base package.

fn_freq

The function is included in the Morefi package Morphological Relationships Fitted by Robust Regression.

The function is detailed below.

fn_freq <- function(df, breaks, right=FALSE){
                    df <- df
                    breaks  <-  breaks
                    fcut  <-  cut(df, breaks, right= right)
                    freq <- table(fcut)
                    }

Examples

In the “df” object, 30 random values between 0.1 and 0.9 are generated. The breaks object is a sequence of equal distances.

df <- runif(n=30, min=0, max=1)
breaks <- seq(0, 1, by= 0.1)

freq <- fn_freq(df, breaks, right= FALSE)
freq

fcut [0,0.1) [0.1,0.2) [0.2,0.3) [0.3,0.4) [0.4,0.5) [0.5,0.6) [0.6,0.7) [0.7,0.8) 5 4 2 2 4 1 4 4 [0.8,0.9) [0.9,1) 2 2

References

Yau C (2024, deck 25). Frequency Distribution of Quantitative Data. R Tutorial An R Introduction to Statistics. https://www.r-tutor.com/elementary-statistics/quantitative-data/frequency-distribution-quantitative-data