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rdata-munging

Sorting data in a dataframe in R

After data munging and using spread, I arrived at the following table: Complaint types and Boroughs

I would like to identify the top 4 issues in each Borough. Sort does not help since there are 4 Boroughs. Any thoughts on how to get?

Solution

  • You can subset the complaint type column with order(column, decreasing=TRUE)[1:4]. It will return the greatest four values in the vector. It is then easy to convert that to whatever form is needed; here a data frame makes sense: 

    lst <- lapply(df[-1], function(col) df[,'Complaint.Type'][order(col, decreasing=T)[1:4]])
as.data.frame(lst)
#     BRONX BROOKLYN MANHATTAN   QUEENS
#1 Facility Facility     Adopt Facility
#2    Abuse    Abuse  Advocate    Adopt
#3     Park      Air      Park     Park
#4 Advocate    Adopt     Abuse Advocate

    Data

    df <- data.frame(Complaint.Type=c('Adopt', 'Advocate', 'Air', 'Abuse', 'Facility','Park'),
                 BRONX=c(0,5, 1, 33, 81, 7),
                 BROOKLYN=c(2,0,100,148,177, 1),
                 MANHATTAN=c(129,49,2,9,1,15),
                 QUEENS=c(50,3,0,3,2469,6))