Passing an input parameter to .data

[ryangarnett]

Hi All,
I am having an issue with one part of my function. Ultimately I am building a custom chart output that allows the user to pass limited parameters, rather than needing to construct the plot each time. The issue I am having is when trying to limit the output legend to have only columns available in the data frame, rather than all colours identified in a list. The specific error is coming from scale_fill_manual(values = gsc_gender_colours[unique(.data${{gender_column}})]) which returns the following error:
Error: unexpected '{' in: " color = "#E4E4E5") + scale_fill_manual(values = gsc_gender_colours[unique(.data${"

What is the best way to:

1. Limit the values displayed in a plot legend based on unique column values rather than a list of potential colours
   OR
2. Pass an input parameter as a column when using .data$

UPDATE

Reproducible Code

# Sample data frame with values
df <- data.frame(gender = c("Female", "Male"), count = c(628, 372))

# Colour list
gender_colours <- list(Female = "#006B35", Male = "#8DC63F", Undisclosed = "#B6B6B6")

# Custom function
create_headcount_gender_chart <- function(.data, headcount_column, gender_column){
  .data %>%
    ggplot2::ggplot() +
      aes(x = 1.5, y = {{headcount_column}}, fill = {{gender_column}}) +
      geom_bar(stat = "identity") +
      coord_polar("y", start = 0) +
      theme_void() +
      xlim(0.2, 2.5) +
      theme(legend.title = element_blank(),
            legend.position = "bottom") +
      geom_text(aes(label = paste(round({{headcount_column}} / sum({{headcount_column}}) * 100, 1), "%")),
                position = position_stack(vjust = 0.5),
                color = "#E4E4E5") +
      scale_fill_manual(values = gender_colours[unique(.data[[gender_column]])])
}

# Testing the function
create_headcount_gender_chart(df,
                              count,
                              gender)

# Error from the function
Error in (function(x, i, exact) if (is.matrix(i)) as.matrix(x)[[i]] else .subset2(x, : object 'gender' not found

[arthur.t]

I think those double curly brackets work in certain tidyverse functions, but may not in unique().

Could try .data[[gender_column]] instead.

[ryangarnett]

Thanks Arthur....great idea...I tried it, but it gave an error...

Error in tbl_subset2(x, j = i, j_arg = substitute(i)) : object 'gender' not found

Any ideas?

[nirgrahamuk]

Hi!

To help us help you, could you please prepare a reproducible example (reprex) illustrating your issue? Please have a look at this guide, to see how to create one:

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.…

[arthur.t]

Did you type gender instead of gender_column?

[ryangarnett]

Thank you, I have since update the question to include a full reproducible example.

[ryangarnett]

Gender is the name of the column. I have since added a fully reproducible example. Thanks!

[nirgrahamuk]

change

scale_fill_manual(values = gender_colours[unique(.data[[gender_column]])])

to

scale_fill_manual(values = gender_colours[unique(.data %>% pull({{gender_column}}))])

[ryangarnett]

@nirgrahamuk

scale_fill_manual(values = gender_colours[unique(.data %>% pull({{gender_column}}))])

Thank you SO much...that work perfectly!
Much appreciated!!