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How to color scatter plot points that meet 2 or more conditions in different columns in R

January 7, 2023

Here is a part of a dataframe that I have

value1	value2	condition1	condition2	condition3
2.3	0.1	FALSE	FALSE	TRUE
3.5	2.6	FALSE	FALSE	TRUE
3.1	2.5	TRUE	TRUE	TRUE
3.2	2.3	FALSE	TRUE	TRUE
2.4	1.1	TRUE	TRUE	FALSE
2.7	2.2	FALSE	TRUE	FALSE
2.5	3	TRUE	FALSE	TRUE
2.9	2	TRUE	TRUE	TRUE
4.2	1	FALSE	FALSE	TRUE
2.2	1.5	FALSE	TRUE	TRUE

I would like to plot a scatter plot of value1 vs value2 and color the points that have 2 or more TRUE conditions,

Do you have any suggestions on how to do this(using ggplot2 and the tidyverse)? Thank you for your time and help

I have tried to group the conditions with group_by but I have not been successful.

>Solution :

We may get the color by using rowSums on the condition columns and then use plot from base R

colr <- ifelse(rowSums(df1[3:5]) > 1, "red", "black")
plot(df1$value1, df1$value2, col = colr, xlab = "value1", ylab = "value2")

Or using tidyverse, create colour column based on rowSums on the logical columns, then use geom_point with colour = colr column and add scale_colour_identity()to use the already existing scaled data

library(dplyr)
library(ggplot2)
df1 %>% 
  mutate(colr = case_when(rowSums(across(starts_with("condition"))) > 1
     ~ "red", TRUE ~ "black")) %>% 
  ggplot(aes(value1, value2, colour = colr)) +
   geom_point() +
    scale_colour_identity()

data

df1 <- structure(list(value1 = c(2.3, 3.5, 3.1, 3.2, 2.4, 2.7, 2.5, 
2.9, 4.2, 2.2), value2 = c(0.1, 2.6, 2.5, 2.3, 1.1, 2.2, 3, 2, 
1, 1.5), condition1 = c(FALSE, FALSE, TRUE, FALSE, TRUE, FALSE, 
TRUE, TRUE, FALSE, FALSE), condition2 = c(FALSE, FALSE, TRUE, 
TRUE, TRUE, TRUE, FALSE, TRUE, FALSE, TRUE), condition3 = c(TRUE, 
TRUE, TRUE, TRUE, FALSE, FALSE, TRUE, TRUE, TRUE, TRUE)),
 class = "data.frame", row.names = c(NA, 
-10L))