如何制作带有 x 轴值不按顺序的值的 R 图

Question

I have the following example dataframe and want to plot columns b (x-axis) and d (y-axis) but based on column a . Meaning I want the rows in b and d that correspond to value 1 in column a to be plotted next to each other (as points or vertical lines) and then similarly for value 2 in column a etc. (all in one graph).

I am having trouble doing this as it would mean the values on the x-axis will increase and decrease/fluctuate.

a <- c(1,1,1,1,1,1,1, 2,2,2,2,2,2,2, 3,3,3,3,3,3,3)
b <- c(1,4,5,7,8,10,13, 5,7,10,11,14,17,23, 3,7,11,16,19,26,29)
d <- c(.4,.15,.76,.07,.18,.11,.12, .23,.45,.25,.11,.16,.2,.5, .48,.9,.13,.75,.4,.98,.3)

df <- data.frame("a" = a, "b" = b, "d" = d)

plot(df$b, df$d)

I have tried basic plotting as shown above (not the results I want) and have tried other methods to relabel the values on the x-axis but that is also incorrect.

Lastly, I am unable to use any R libraries as I cannot download them on the computer I am using.

Thank you in advance for any help!

Answer 1

Not sure if I understand the question properly, but perhaps plotting the interaction of "a" and "b" would work?

a <- c(1,1,1,1,1,1,1, 2,2,2,2,2,2,2, 3,3,3,3,3,3,3)
b <- c(1,4,5,7,8,10,13, 5,7,10,11,14,17,23, 3,7,11,16,19,26,29)
d <- c(.4,.15,.76,.07,.18,.11,.12, .23,.45,.25,.11,.16,.2,.5, .48,.9,.13,.75,.4,.98,.3)

df <- data.frame("a" = a, "b" = interaction(b, a), "d" = d)
df$b <- factor(df$b, levels = df$b)

png("test.png", width = 900, height = 400, units = "px")
plot(df$b, df$d)
dev.off()

Edit

Or maybe remove the x-axis labels and add them in 'manually'?

a <- c(1,1,1,1,1,1,1, 2,2,2,2,2,2,2, 3,3,3,3,3,3,3)
b <- c(1,4,5,7,8,10,13, 5,7,10,11,14,17,23, 3,7,11,16,19,26,29)
d <- c(.4,.15,.76,.07,.18,.11,.12, .23,.45,.25,.11,.16,.2,.5, .48,.9,.13,.75,.4,.98,.3)

df <- data.frame("a" = a, "b" = b, "d" = d)

png("test.png", width = 900, height = 400, units = "px")
plot(seq_along(df$b), df$d, xaxt = "none")
axis(1, at = seq_along(df$b), labels = df$b)
dev.off()

Edit 2

Another approach that may better "preserve the spacing" of the x-axis is to split the dataframe and plot each group separately:

a <- c(1,1,1,1,1,1,1, 2,2,2,2,2,2,2, 3,3,3,3,3,3,3)
b <- c(1,4,5,7,8,10,13, 5,7,10,11,14,17,23, 3,7,11,16,19,26,29)
d <- c(.4,.15,.76,.07,.18,.11,.12, .23,.45,.25,.11,.16,.2,.5, .48,.9,.13,.75,.4,.98,.3)

df <- data.frame("a" = a, "b" = b, "d" = d)

split_df <- split(df, df$a)

par(mfrow = c(1, 3), mar = c(2, 2, 1, 1))
plot(split_df$`1`$b, split_df$`1`$d, ylim = c(0, 1))
plot(split_df$`2`$b, split_df$`2`$d, ylim = c(0, 1))
plot(split_df$`3`$b, split_df$`3`$d, ylim = c(0, 1))

^{Created on 2021-10-15 by the reprex package (v2.0.1)}