scale_colour_gradient2 {ggplot2} | R Documentation |
Diverging colour gradient
scale_colour_gradient2(..., low = muted("red"), mid = "white", high = muted("blue"), midpoint = 0, space = "rgb", na.value = "grey50", guide = "colourbar") scale_fill_gradient2(..., low = muted("red"), mid = "white", high = muted("blue"), midpoint = 0, space = "rgb", na.value = "grey50", guide = "colourbar") scale_color_gradient2(..., low = muted("red"), mid = "white", high = muted("blue"), midpoint = 0, space = "rgb", na.value = "grey50", guide = "colourbar")
midpoint |
The midpoint (in data value) of the diverging scale. Defaults to 0. |
guide |
Type of legend. Use |
... |
Other arguments passed on to
|
na.value |
Colour to use for missing values |
low |
colour for low end of gradient. |
mid |
colour for mid point |
high |
colour for high end of gradient. |
space |
colour space in which to calculate gradient. "Lab" usually best unless gradient goes through white. |
Other colour scales: scale_color_brewer
,
scale_color_continuous
,
scale_color_discrete
,
scale_color_gradient
,
scale_color_gradientn
,
scale_color_grey
,
scale_color_hue
,
scale_colour_brewer
,
scale_colour_continuous
,
scale_colour_discrete
,
scale_colour_gradient
,
scale_colour_gradientn
,
scale_colour_grey
,
scale_colour_hue
,
scale_fill_brewer
,
scale_fill_continuous
,
scale_fill_discrete
,
scale_fill_gradient
,
scale_fill_gradientn
,
scale_fill_grey
,
scale_fill_hue
dsub <- subset(diamonds, x > 5 & x < 6 & y > 5 & y < 6) dsub$diff <- with(dsub, sqrt(abs(x-y))* sign(x-y)) (d <- qplot(x, y, data=dsub, colour=diff)) d + scale_colour_gradient2() # Change scale name d + scale_colour_gradient2(expression(sqrt(abs(x - y)))) d + scale_colour_gradient2("Difference\nbetween\nwidth and\nheight") # Change limits and colours d + scale_colour_gradient2(limits=c(-0.2, 0.2)) # Using "muted" colours makes for pleasant graphics # (and they have better perceptual properties too) library(scales) # for muted d + scale_colour_gradient2(low="red", high="blue") d + scale_colour_gradient2(low=muted("red"), high=muted("blue")) # Using the Lab colour space also improves perceptual properties # at the price of slightly slower operation d + scale_colour_gradient2(space="Lab") # About 5% of males are red-green colour blind, so it's a good # idea to avoid that combination d + scale_colour_gradient2(high=muted("green")) # We can also make the middle stand out d + scale_colour_gradient2(mid=muted("green"), high="white", low="white") # or use a non zero mid point (d <- qplot(carat, price, data=diamonds, colour=price/carat)) d + scale_colour_gradient2(midpoint=mean(diamonds$price / diamonds$carat)) # Fill gradients work much the same way p <- qplot(letters[1:5], 1:5, fill= c(-3, 3, 5, 2, -2), geom="bar") p + scale_fill_gradient2("fill") # Note how positive and negative values of the same magnitude # have similar intensity