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Trouble with R's ggplot2 not displaying legend for custom color scale

👀 Views: 61 đŸ’Ŧ Answers: 1 📅 Created: 2025-06-10
ggplot2 data-visualization color R

I'm learning this framework and I'm migrating some code and Can someone help me understand After trying multiple solutions online, I still can't figure this out..... I'm having trouble with a ggplot2 plot where the legend is not displaying correctly for my custom color scale. I'm using ggplot2 version 3.3.5 and trying to create a scatter plot with points colored based on a categorical variable. Initially, I set the colors using `scale_color_manual`, but the legend doesn't show up as expected. Here's the code I'm using: ```R library(ggplot2) # Sample data set.seed(42) data <- data.frame( x = rnorm(100), y = rnorm(100), category = sample(c('A', 'B', 'C'), 100, replace = TRUE) ) # Plot code p <- ggplot(data, aes(x = x, y = y, color = category)) + geom_point(size = 3) + scale_color_manual(values = c('A' = 'red', 'B' = 'blue', 'C' = 'green')) + theme_minimal() print(p) ``` When I run this code, the points are colored correctly, but I don't see a legend for the categories. I've tried adding `guides(color = guide_legend())` but it still doesn't appear. I suspect it might have something to do with how I am specifying the colors or the aesthetic mappings. Have I missed something in the configuration? Any help would be appreciated! For context: I'm using R on Linux. Is there a better approach? I've been using R for about a year now. Any ideas what could be causing this? This is happening in both development and production on Ubuntu 20.04. Any pointers in the right direction?