带图例的条形图R中的列

Question

I'm trying to plot a bar plot of a data frame with n columns and m rows. One of the rows houses the category, and I would like the barplot colors to be based on which category the column belongs to.

Example :

example = as.data.frame(matrix(1:100, nrow = 1, ncol = 5),
                    dimnames(list(NULL, paste0('ColumnName_', 1:5)))) 
category = as.data.frame(matrix(c('cat.1', 'cat.1', 'cat.2', 'cat.4', 'cat.3'),
                            nrow = 1, ncol = 5), 
                     dimnames(list(NULL, paste0('ColumnName_', 1:5)))) 
example_df = rbind(example, category)
rownames(example_df) <- c('values 1', 'categories')

I'd like a barplot with the column names on the x axis, the and the values 1 row as data, but collored with respect to the category row.

Thank you.

Answer 1

Try something like this. Note how the data is structured to work well with ggplot.

library(ggplot)
data <- data.frame(animal = c("Cat", "Dog", "Shark", "Fish"), 
                   home = c("land", "land", "sea", "sea"), 
                   age = c(2,7,9,5))

ggplot(data, aes(x = animal, y = age, fill = home)) + 
    geom_bar(stat = "identity")

Answer 2

Ok, using your code, and restructuring into tidy format:

example = as.data.frame(matrix(1:100, nrow = 1, ncol = 5),
                        dimnames(list(NULL, paste0('ColumnName_', 1:5)))) 
category = as.data.frame(matrix(c('cat.1', 'cat.1', 'cat.2', 'cat.4', 'cat.3'),
                                nrow = 1, ncol = 5), 
                         dimnames(list(NULL, paste0('ColumnName_', 1:5)))) 

example_df = rbind(example, category)
rownames(example_df) <- c('values 1', 'categories')

example_df <- as.data.frame(t(example_df))
example_df["names"] <- rownames(example_df)
ggplot(example_df, aes(x = names, y = `values 1`, fill = categories)) + geom_bar(stat = "identity")