Need help with "Error in object[[i]]: object of type 'closure' is not subsettable" error.

[grim_11]

Hi I am learning R from coursera and while doing an assignment I am getting the error stated in the title.
Can someone please help me?
The code snippet is as follows,

preprocess_covid_data_frame <- function(data_frame) {
    
    shape <- dim(data_frame)

    # Remove the World row
    data_frame<-data_frame[!(data_frame$`Country or region`=="World"),]
    # Remove the last row
    data_frame <- data_frame[1:172, ]
    
    # We dont need the Units and Ref columns, so can be removed
    data_frame["Ref."] <- NULL
    data_frame["Units[b]"] <- NULL
    
    # Renaming the columns
    names(data_frame) <- c("country", "date", "tested", "confirmed", "confirmed.tested.ratio", "tested.population.ratio", "confirmed.population.ratio")
    
    # Convert column data types
    data_frame$country <- as.factor(data_frame$country)
    data_frame$date <- as.factor(data_frame$date)
    data_frame$tested <- as.numeric(gsub(",","",data_frame$tested))
    data_frame$confirmed <- as.numeric(gsub(",","",data_frame$confirmed))
    data_frame$'confirmed.tested.ratio' <- as.numeric(gsub(",","",data_frame$`confirmed.tested.ratio`))
    data_frame$'tested.population.ratio' <- as.numeric(gsub(",","",data_frame$`tested.population.ratio`))
    data_frame$'confirmed.population.ratio' <- as.numeric(gsub(",","",data_frame$`confirmed.population.ratio`))
    
    return(data_frame)
}

[technocrat]

@grim_11

data_frame <- data_frame[1:172, ]

data_frame is also the name of a function in the {dplyr} package. When a function is given no argument, it’s called a closure, which is not a vector or a matrix, so it can’t be subset. If you have loaded {dplyr} directly or with {tidyverse} that’s what’s happening.

In general avoid names of functions, such as data, df, c when naming your own objects.

[grim_11]

Hi,
Thank you for your response, so I tried changing "data_frame" to "final_table" and tried to run the code and the same error is reappearing.
This code snippet is something I don't know in depth as it is a part of an assignment that was provided to me and now i am stuck and cant proceed further till this step isnt complete.

[FJCC]

The function works for me with invented data. Please post the output

summary(DF)

where you replace DF with the data you are using.

Here is what I ran.

#Invent data
DF <- data.frame(Ref.= rep("A",173),`Units[b]` = rep("B",173),
                 `Country or region` = rep("C",173),
date = rep("D",173),tested = rep("1,234",173),
confirmed = rep("2,345",173),
confirmed.tested.ratio = rep("3,456",173),
tested.population.ratio=rep("4,567",173),
confirmed.population.ratio = rep("7,234",173),check.names = FALSE)
head(DF)
#>   Ref. Units[b] Country or region date tested confirmed confirmed.tested.ratio
#> 1    A        B                 C    D  1,234     2,345                  3,456
#> 2    A        B                 C    D  1,234     2,345                  3,456
#> 3    A        B                 C    D  1,234     2,345                  3,456
#> 4    A        B                 C    D  1,234     2,345                  3,456
#> 5    A        B                 C    D  1,234     2,345                  3,456
#> 6    A        B                 C    D  1,234     2,345                  3,456
#>   tested.population.ratio confirmed.population.ratio
#> 1                   4,567                      7,234
#> 2                   4,567                      7,234
#> 3                   4,567                      7,234
#> 4                   4,567                      7,234
#> 5                   4,567                      7,234
#> 6                   4,567                      7,234

preprocess_covid_data_frame <- function(data_frame) {
  
  shape <- dim(data_frame)
  
  # Remove the World row
  data_frame<-data_frame[!(data_frame$`Country or region`=="World"),]
  # Remove the last row
  data_frame <- data_frame[1:172, ]
  
  # We dont need the Units and Ref columns, so can be removed
  data_frame["Ref."] <- NULL
  data_frame["Units[b]"] <- NULL
  
  # Renaming the columns
  names(data_frame) <- c("country", "date", "tested", "confirmed", "confirmed.tested.ratio", "tested.population.ratio", "confirmed.population.ratio")
  
  # Convert column data types
  data_frame$country <- as.factor(data_frame$country)
  data_frame$date <- as.factor(data_frame$date)
  data_frame$tested <- as.numeric(gsub(",","",data_frame$tested))
  data_frame$confirmed <- as.numeric(gsub(",","",data_frame$confirmed))
  data_frame$'confirmed.tested.ratio' <- as.numeric(gsub(",","",data_frame$`confirmed.tested.ratio`))
  data_frame$'tested.population.ratio' <- as.numeric(gsub(",","",data_frame$`tested.population.ratio`))
  data_frame$'confirmed.population.ratio' <- as.numeric(gsub(",","",data_frame$`confirmed.population.ratio`))
  
  return(data_frame)
}
OUT <- preprocess_covid_data_frame(DF)
summary(OUT)
#>  country date        tested       confirmed    confirmed.tested.ratio
#>  C:172   D:172   Min.   :1234   Min.   :2345   Min.   :3456          
#>                  1st Qu.:1234   1st Qu.:2345   1st Qu.:3456          
#>                  Median :1234   Median :2345   Median :3456          
#>                  Mean   :1234   Mean   :2345   Mean   :3456          
#>                  3rd Qu.:1234   3rd Qu.:2345   3rd Qu.:3456          
#>                  Max.   :1234   Max.   :2345   Max.   :3456          
#>  tested.population.ratio confirmed.population.ratio
#>  Min.   :4567            Min.   :7234              
#>  1st Qu.:4567            1st Qu.:7234              
#>  Median :4567            Median :7234              
#>  Mean   :4567            Mean   :7234              
#>  3rd Qu.:4567            3rd Qu.:7234              
#>  Max.   :4567            Max.   :7234

^{Created on 2022-01-02 by the reprex package (v2.0.1)}

[grim_11]

Thank you, I figured it out, I wasn't putting the (DF) in this

@FJCC

OUT <- preprocess_covid_data_frame(DF)

I didnt know the relevance of it. Thank you for your help.