How to change name on column within a function?

July 30, 2022

This is a generic question related to functions:

Let’s say I have the following function with random code within brackets. I found this code from a earlier thread from today: Add a column to function with fixed variable

read_prem_league <- function(year) { 
"https://en.wikipedia.org/wiki/" %>%
  paste0(year - 1, "-", substr(as.character(year), 3, 4), "_Premier_League") %>%
  read_html() %>% 
  html_table() %>% 
  getElement(5)
}

read_prem_league(2015)

Which generates the following tibble:

#> # A tibble: 20 x 11
#>      Pos Team                   Pld     W     D     L    GF    GA GD      Pts
#>    <int> <chr>                <int> <int> <int> <int> <int> <int> <chr> <int>
#>  1     1 Manchester City (C)     38    27     5     6    83    32 +51      86
#>  2     2 Manchester United       38    21    11     6    73    44 +29      74
#>  3     3 Liverpool               38    20     9     9    68    42 +26      69
#>  4     4 Chelsea                 38    19    10     9    58    36 +22      67
#>  5     5 Leicester City          38    20     6    12    68    50 +18      66
#>  6     6 West Ham United         38    19     8    11    62    47 +15      65
#>  7     7 Tottenham Hotspur       38    18     8    12    68    45 +23      62
#>  8     8 Arsenal                 38    18     7    13    55    39 +16      61
#>  9     9 Leeds United            38    18     5    15    62    54 +8       59
#> 10    10 Everton                 38    17     8    13    47    48 -1       59
#> 11    11 Aston Villa             38    16     7    15    55    46 +9       55
#> 12    12 Newcastle United        38    12     9    17    46    62 -16      45
#> 13    13 Wolverhampton Wande~    38    12     9    17    36    52 -16      45
#> 14    14 Crystal Palace          38    12     8    18    41    66 -25      44
#> 15    15 Southampton             38    12     7    19    47    68 -21      43
#> 16    16 Brighton & Hove Alb~    38     9    14    15    40    46 -6       41
#> 17    17 Burnley                 38    10     9    19    33    55 -22      39
#> 18    18 Fulham (R)              38     5    13    20    27    53 -26      28
#> 19    19 West Bromwich Albio~    38     5    11    22    35    76 -41      26
#> 20    20 Sheffield United (R)    38     7     2    29    20    63 -43      23
#> # ... with 1 more variable: `Qualification or relegation` <chr>

I would like to change name of Team column to Club so it always has the name Club. I want to find a general code that works for column 2 in other functions aswell as there are functions where the data are same but column names differs (and I want one column name).

Something similar to below code that was brought as an previous answer is what I’m looking for:

    dat <- read.csv(url)
    names(dat)[2] <- "year"
    dat

>Solution :

You can rename by index

read_prem_league <- function(year) { 
"https://en.wikipedia.org/wiki/" %>%
  paste0(year - 1, "-", substr(as.character(year), 3, 4), "_Premier_League") %>%
  read_html() %>% 
  html_table() %>% 
  getElement(5) %>% 
  rename(Club=2)
}