I have been copying the code from: Chang, 2012, R Graphics Cookbook: Practical Recipes for Visualizing Data. pg, 46-47
Which is this:
ggplot(prac1, aes(x=pos1, y=pos2)) +
geom_segment(aes(yend=pos2), xend=0, colour="grey50") +
geom_point(size=3, aes(colour=lg)) +
scale_colour_brewer(palette="Set1", limits=c("NL","AL")) +
theme_bw() +
theme(panel.grid.major.y = element_blank(), # No horizontal grid lines
legend.position=c(1, 0.55), # Put legend inside plot area
legend.justification=c(1, 0.5))
OR
ggplot(prac1, aes(x=pos1, y=pos2)) +
geom_segment(aes(yend=pos2), xend=0, colour="grey50") +
geom_point(size=3, aes(colour=lg)) +
scale_colour_brewer(palette="Set1", limits=c("NL","AL"), guide=FALSE) +
theme_bw() +
theme(panel.grid.major.y = element_blank()) +
facet_grid(lg ~ ., scales="free_y", space="free")
One of the two errors are returned:
(1) Error: At least one layer must contain all faceting variables: `lg`.
* Plot is missing `lg`
* Layer 1 is missing `lg`
* Layer 2 is missing `lg
(2) Error in FUN(X[[i]], ...) : object 'lg' not found
My data structure:
str(prac1)
'data.frame': 32 obs. of 3 variables:
$ Common.Name : Factor w/ 32 levels "Blackbird","Blue Tit ",..: 8 1 23 3 7 28 12 31 25 17 ...
$ G.vs.S : Factor w/ 2 levels "G","S": 1 1 1 1 2 2 2 1 2 2 ...
$ Average.weight: num 21.2 101.8 75 22.5 47 ...
REPRODUCIBLE CODE:
prac1 <- dstructure(list(Common.Name = structure(c(8L, 1L, 23L, 3L, 7L,
28L, 12L, 31L, 25L, 17L, 32L, 22L, 15L, 19L, 6L, 11L, 21L, 26L,
9L, 29L, 14L, 13L, 27L, 16L, 30L, 20L, 2L, 10L, 18L, 5L, 4L,
24L), .Label = c("Blackbird", "Blue Tit ", "Bullfinch", "Buzzard",
"Chaffinch ", "Common Whitethroat", "Corn Bunting", "Dunnock",
"Goldfinch", "Great tit ", "Greenfinch", "Grey Partridge", "House martin",
"Jackdaw", "Kestrel", "Lapwing ", "Linnet", "Long-tailed Tit ",
"Reed Bunting", "Robin ", "Rook", "Skylark", "Song Thrush", "Sparrowhawk",
"Starling", "Stock dove", "Swallow", "Turtle Dove", "Woodpigeon",
"Wren ", "Yellow Wagtail", "Yellowhammer"), class = "factor"),
G.vs.S = structure(c(1L, 1L, 1L, 1L, 2L, 2L, 2L, 1L, 2L,
2L, 2L, 2L, 1L, 1L, 2L, 1L, 1L, 2L, 2L, 1L, 1L, 1L, 1L, 2L,
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L), .Label = c("G", "S"), class = "factor"),
Average.weight = c(21.17, 101.8, 74.95, 22.51, 47, 156.8,
390, 17.55, 84.99, 18.79, 25.89, 38.56, 205.5, 19.18, 13.76,
27.66, 452.3, 326.3, 15.8, 507.4, 231.8, 17.81, 19.9, 250.3,
9.91, 18.98, 10.88, 18.61, 7.78, 21.81, 828.2, 205)), row.names = c(NA,
-32L), class = "data.frame")
My X and Y variables:
pos1 <- prac1$Common.Name
pos2 <- prac1$Average.weight
How can I fix the error, the end result should have a graph looking like this but with my data:
