issue 3451: scale_manual throws unexpected error when na.values given and insufficient values provided
The case 1 and 2 of the following did not work at that time. But, then insufficient values are allowed now. So, none of the following errors now.
df <- data.frame(x = 1, y = 1:3, z = factor(c("a","b", NA), exclude = NULL))
p <- qplot(x, y, data = df, colour = z)
p1 <- p + scale_colour_manual(values = c("a" = "black")) +
ggtitle("Case 1: Insufficient values error (as expected)")
p2 <- p + scale_colour_manual(values = c("a" = "black"), na.value = "grey") +
ggtitle("Case 2: Insufficient values error (not as expected)")
p3 <- p + scale_colour_manual(values = c("a" = "black", "c" = "white"), na.value = "grey") +
ggtitle('Case 3: plot with "b" points given na.value (as expected)')
patchwork::wrap_plots(p1, p2, p3, ncol = 1)
The plot should not error when the data contains fewer values than the specified levels.
It errors.
df <- data.frame(
x = rep(1:10, 2),
y = rnorm(20),
group = rep(c("B", "C"), each = 10) # no A here
)
ggplot(df, aes(x, y, colour = group)) +
geom_point(size = 3) +
scale_colour_manual(values = c(A = "blue", B = "green", C = "red")) +
guides(
color = guide_legend(
override.aes = list(
alpha = rep(0.6, length(unique(df$group))),
size = rep(6, length(unique(df$group)))
)
)
)
#> Error in `[[<-.data.frame`(`*tmp*`, i, value = c(0.6, 0.6)): replacement has 2 rows, data has 3
The legend should show levels that don’t exist in values only when
- The values are factors
- The levels of the scales exist in the levels of the factors
- drop = FALSE is specified
So, only the case 3 should show the blue legend for “b”.
All the plots show the blue legend.
color_map <- list(r = "red", g = "green", b = "blue")
df <- dplyr::mutate(
randu,
color_key = factor(dplyr::if_else(x > y, "r", "g")),
color_key2 = factor(dplyr::if_else(x > y, "r", "g"), levels = c("r", "g", "b"))
)
p1 <- ggplot(df, aes(x = x, y = y, fill = color_key)) +
scale_fill_manual(values = color_map) +
geom_point(shape = 21, size = 7) +
ggtitle("Case 1: character")
p2 <- ggplot(df, aes(x = x, y = y, fill = color_key2)) +
scale_fill_manual(values = color_map) +
geom_point(shape = 21, size = 7) +
ggtitle("Case 2: factor")
p3 <- ggplot(df, aes(x = x, y = y, fill = color_key2)) +
scale_fill_manual(values = color_map, drop = FALSE) +
geom_point(shape = 21, size = 7) +
ggtitle("Case 3: factor, drop = FALSE")
patchwork::wrap_plots(p1, p2, p3, ncol = 1)
# c.f. when `limits` is beyond the range of `values`, it fails
ggplot(df, aes(x = x, y = y, fill = color_key2)) +
scale_fill_manual(values = color_map, drop = FALSE, limits = c("r", "g", "b", "a")) +
geom_point(shape = 21, size = 7)
#> Error: Insufficient values in manual scale. 4 needed but only 3 provided.
Created on 2021-09-20 by the reprex package (v2.0.1)
