问题
I am constructing a facet_grid using stat_hexbin however I would like the alpha value to be independent for each of the facet plots.
I am currently using the following code:
ggplot (data, aes (x, y , fill = z)) +
stat_binhex(bins=20, aes(alpha = ..count..)) +
facet_grid(. ~ z) +
guides(alpha = F) +
coord_equal() +
theme_bw()
which produces the following plot:
However, the alpha value, which is defined by ..count.. doesn't work when applied outside of the aes within stat_binhex.
I would like to show that there is some clustering in the 90 grouping on the right, around the (100,0) region, but the hexes are very pale, since there is such heavy clustering around (0,0) in the 10 grouping (leftmost plot) which skews the alpha.
Main question: How can I make the alpha independent for each facet, but still connected to count/density to better show the clustering in '70' and '90' groups?
Many thanks!
Data:
# rounded x and y, from 2 days of 365
structure(list(x = c(-24, 41, 43, 14, 9, 30, 8, -14, -45, 42,
65, 39, 43, 49, 39, 61, -53, -16, 29, 27, 9, 6, -61, 20, 5, -30,
-10, 75, 94, 28, 70, 44, -11, 26, 29, 33, 26, -35, 20, 40, 7,
4, 14, 4, -41, -7, -21, 95, 20, 50, 63, 31, 47, 19, 20, 19, 23,
-25, 29, -8, -73, 13, -82, 4, -29, 3, 9, 3, 35, 45, 64, -14,
-4, 34, 13, 12, 20, 13, 15, -17, 12, 19, -55, -49, 95, -19, 45,
94, 23, 29, 22, -91, -39, -35, -3, 63, 2, 5, 30, 62, 1, 4, -61,
-6, -2, 5, -26, -23, 5, 6, 8, 45, 104, -7, 8, 44, -43, -8, 9,
12, 29, 30, 69, 90, 12, -28, -10, -9, 49, 60, 32, 43, -11, 12,
28, 91, 11, 13, 43, 61, 11, 12, 28, 31, 47, 12, 13, 30, 46, 66,
98, 11, 12, 29, 31, 44, 64, -11, 14, 48, 62, 96, 10, 11, 12,
29, 67, 30, 93, -10, -9, 44, 101, -28, 34, 46, 10, 27, 30, 61,
8, 24, -7, -2, 52, 65, 5, -43, 41, 45, 91, -24, -23, 37, 73,
97, -61, 63, 57, 52, -37, -35, 19, 24, 110, -91, -5, -17, 95,
13, 85, -52, -50, 78, 30, 37, -8, -27, 19, -78, -75, 52, 42,
-11, -37, 27, 62, 78, -16, -56, 41), y = c(-100, -95, -95, -92,
-88, -86, -84, -82, -81, -78, -73, -72, -71, -70, -69, -68, -67,
-67, -64, -63, -62, -59, -58, -57, -56, -54, -54, -54, -54, -52,
-52, -49, -48, -48, -48, -47, -46, -45, -45, -45, -44, -42, -41,
-40, -39, -39, -38, -38, -37, -36, -36, -35, -35, -34, -34, -33,
-33, -32, -32, -31, -30, -30, -29, -29, -28, -27, -27, -26, -26,
-26, -26, -25, -25, -25, -24, -23, -23, -22, -22, -21, -21, -21,
-20, -20, -19, -18, -18, -18, -17, -17, -16, -14, -14, -14, -13,
-13, -12, -12, -12, -12, -11, -11, -10, -10, -10, -10, -9, -9,
-9, -9, -9, -9, -9, -8, -8, -8, -7, -7, -7, -7, -6, -6, -6, -6,
-5, -4, -4, -4, -4, -4, -3, -3, -2, -2, -2, -2, -1, -1, -1, -1,
0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3,
3, 4, 4, 4, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 8, 9, 9, 9, 9, 10,
10, 11, 11, 11, 11, 12, 13, 14, 14, 14, 15, 15, 15, 16, 16, 18,
19, 20, 21, 23, 23, 24, 24, 24, 26, 27, 28, 28, 29, 30, 32, 32,
32, 36, 36, 41, 42, 44, 48, 48, 50, 51, 57, 60, 62, 76, 76, 85,
89, 93), z = c(90, 90, 90, 90, 90, 90, 90, 90, 90, 90, 90, 90,
90, 90, 90, 90, 90, 70, 70, 70, 70, 70, 90, 70, 70, 70, 70, 90,
90, 70, 90, 70, 50, 70, 70, 70, 70, 70, 50, 70, 50, 50, 50, 50,
70, 50, 50, 90, 50, 70, 70, 50, 70, 50, 50, 50, 50, 50, 50, 30,
90, 30, 90, 30, 50, 30, 30, 30, 50, 50, 70, 30, 30, 50, 30, 30,
30, 30, 30, 30, 30, 30, 70, 70, 90, 30, 50, 90, 30, 30, 30, 90,
50, 50, 10, 70, 10, 10, 30, 70, 10, 10, 70, 10, 10, 10, 30, 30,
10, 10, 10, 50, 90, 10, 10, 50, 50, 10, 10, 10, 30, 30, 70, 90,
10, 30, 10, 10, 50, 70, 30, 50, 10, 10, 30, 90, 10, 10, 50, 70,
10, 10, 30, 30, 50, 10, 10, 30, 50, 70, 90, 10, 10, 30, 30, 50,
70, 10, 10, 50, 70, 90, 10, 10, 10, 30, 70, 30, 90, 10, 10, 50,
90, 30, 30, 50, 10, 30, 30, 70, 10, 30, 10, 10, 50, 70, 10, 50,
50, 50, 90, 30, 30, 50, 70, 90, 70, 70, 70, 70, 50, 50, 30, 30,
90, 90, 30, 30, 90, 30, 90, 70, 70, 90, 50, 50, 50, 50, 50, 90,
90, 70, 70, 70, 70, 70, 90, 90, 90, 90, 90)), .Names = c("x",
"y", "z"), row.names = c(NA, -231L), class = c("data.table",
"data.frame"), .internal.selfref = <pointer: 0x0000000000330788>)
来源：https://stackoverflow.com/questions/42433116/independent-alpha-for-each-plot-within-facet-grid-based-on-density