Creating an equal depth bin

[Ron256]

Hi all,

I have a task where I am creating an equal depth bin. My goal is to come up with the following bin:

[3, 4), [5, 6] and [7, 8]

library(classInt)
quality <- c(3, 4, 5, 6, 7, 8)
df.wine <- data.frame(quality)
w <- classIntervals(df.wine$quality
                    , n=3
                    , style = "pretty"
                    )
w

But when I run my R code I get this

[2,4) [4,6) [6,8]

I request someone to point me in the right direction.

Thank you,

Ron

[jrkrideau]

Can you supply us with your code and some sample data.

For some suggestions see:

FAQ: How to do a minimal reproducible example ( reprex ) for beginners

A minimal reproducible example consists of the following items: A minimal dataset, necessary to reproduce the issue The minimal runnable code necessary to reproduce the issue, which can be run on the given dataset, and including the necessary information on the used packages. Let's quickly go over each one of these with examples: Minimal Dataset (Sample Data) You need to provide a data frame that is small enough to be (reasonably) pasted on a post, but big enough to reproduce your issue. Let's say, as an example, that you are working with the iris data frame head(iris) #> Sepal.Length Sepal.Width Petal.Length Petal.Width Species #> 1 5.1 3.5 1.4 0.…

[Jwvz001]

Hi Ron,

What you get is correct, it seems to me. R treats your vector as a numeric, so a continuous interval ranging from 3 to 8. The binning therefore is continuous. R returns is the interval splits, not where the elements of your vector go. Are you probably looking for following explanation (I used cut-function, not your package)?

class(quality)                                                                
# [1] "numeric"                                                               
cut(quality, breaks = c(3,4,6,8), include.lowest = TRUE)                      
# [1] [3,4] [3,4] (4,6] (4,6] (6,8] (6,8]                                     
# Levels: [3,4] (4,6] (6,8]                                                   
                                                                              
table(cut(quality, breaks = c(3,4,6,8), include.lowest = TRUE) )              
#                                                                             
# [3,4] (4,6] (6,8]                                                           
#     2     2     2                                                           
                                                                              
#use split to see the element-split                                           
f  <- as.factor(cut(quality, breaks = c(3,4,6,8), include.lowest = TRUE) )    
split(quality, f)                                                             
# $`[3,4]`                                                                    
# [1] 3 4                                                                     
#                                                                             
# $`(4,6]`                                                                    
# [1] 5 6                                                                     
#                                                                             
# $`(6,8]`                                                                    
# [1] 7 8                                                                     
#                                                                             

Otherwise, as @jrkrideau suggests, you need to provide more information for what you trying to achieve.

Hope this helps, JW

[Ron256]

Hi JW,

Thanks for the information. I will definitely do what JW suggested next time I ask a question.

The cut package does a better a job in making me understand what I was trying to achieve.

Thank you,

Ron

[Jwvz001]

Hi Ron,

Glad to be of help. Note that cut is not a package, but a base R function, so always available! If you are looking to understand what is going on, looking into base R solutions for common operations, would be my general recommendation. Gives a feeling what is going on under the hood.

Welcome and have fun withR!

JW