如何在R中的传单中为数值变量设置不对称颜色渐变
How to set up asymmetrical color gradient for a numerical variable in leaflet in R
我想让传单调色板居中为零(红-白-绿发散)。我已经尝试了 中所说的内容。当我尝试这种手动创建颜色时,我得到了红绿散度但无法将其居中为零。
我的代码
regions@data <- data.frame(region <- c("APAC (excl. China)", "Africa",
"Americas", "Europe", "Greater China", "Middle East"),
change_targeted <- c(36,-21,25,4,173,34))
color = "#666"
weight = 0.5
opacity = 1
fillOpacity = 1
dashArray = ""
hl_color = "black"
hl_weight = 1
hl_dashArray = ""
library(RColorBrewer)
nHalf = nrow(regions@data)/2
Min = min(regions@data[,"change_targeted"])
Max = max(regions@data[,"change_targeted"])
Thresh = 0
## Make vector of colors for values below threshold
rc1 = colorRampPalette(colors = c("red", "white"), space="Lab")(nHalf)
## Make vector of colors for values above threshold
rc2 = colorRampPalette(colors = c("white", "green"), space="Lab")(nHalf)
rampcols = c(rc1, rc2)
## In your example, this line sets the color for values between 49 and 51.
rampcols[c(nHalf, nHalf+1)] = rgb(t(col2rgb("white")), maxColorValue=256)
rb1 = seq(Min, Thresh, length.out=nHalf+1)
rb2 = seq(Thresh, Max, length.out=nHalf+1)[-1]
rampbreaks = c(rb1, rb2)
pal <- colorNumeric(
palette = rampcols, #"Blues", #YlGnBu,YlOrRd
domain = regions@data$change_targeted)
leaflet(regions, options = leafletOptions(zoomControl = FALSE,
attributionControl=FALSE)) %>%
addPolygons(color = color,
weight = weight, #smoothFactor = 0.5,
opacity = opacity, fillOpacity = fillOpacity,
dashArray = dashArray,
fillColor = ~pal(change_targeted),
highlightOptions = highlightOptions(color = hl_color,
weight = hl_weight,
dashArray = hl_dashArray,
bringToFront = TRUE),
label =
~as.character(paste0(region,"",round(change_targeted,1),"%")),
labelOptions = labelOptions(noHide = T, textOnly = F,
direction = "left",
textsize = "12px")) %>%
setView(35, 36, 0.5) %>%
addLegend("bottomright", pal = pal, values = ~change_targeted,
title = NULL,
labFormat = labelFormat(suffix = "%"), opacity=1)
我的地图
理想情况下,我希望只有非洲有红色,其余地区有白色到绿色的调色板
由于我没有你的数据、地区,我选择使用我一直在使用的虚拟数据来回答 Stack Overflow 上的一些问题。我希望你不介意。乔希的回答基本上给了你正确的方向。您可能误解了他的代码。在 that question 中,他创建并组合了两个调色板。然后,他手动将中点颜色设置为绿色。你想知道他在每个调色板中创建了 50 种颜色。你的故事是另一个故事;你需要扭曲他的回答。您想要使用红色、白色和绿色创建不对称的颜色范围。您需要创建介于红色和白色之间(即介于 -20 和 0 之间)的 20 种颜色,以及介于白色和绿色之间(即介于 0 和 180 之间)的 180 种颜色。您可以使用实际数据更改这些范围。
现在您想使用 Josh 的代码。您不必全部使用它。您所需要的只是创建两个调色板并将它们组合起来。完成后,您就可以开始了。在下面的代码中,我跳过了您的突出显示选项以尽量减少这种情况。
library(raster)
library(dplyr)
library(leaflet)
library(RColorBrewer)
### Get UK polygon data
UK <- getData("GADM", country = "GB", level = 2)
### Create dummy data
set.seed(111)
mydf <- data.frame(place = unique(UK$NAME_2),
value = sample(x = -20:180, size = n_distinct(UK$NAME_2), replace = TRUE))
### Create an asymmetric color range
## Make vector of colors for values smaller than 0 (20 colors)
rc1 <- colorRampPalette(colors = c("red", "white"), space = "Lab")(20)
## Make vector of colors for values larger than 0 (180 colors)
rc2 <- colorRampPalette(colors = c("white", "green"), space = "Lab")(180)
## Combine the two color palettes
rampcols <- c(rc1, rc2)
mypal <- colorNumeric(palette = rampcols, domain = mydf$value)
## If you want to preview the color range, run the following code
previewColors(colorNumeric(palette = rampcols, domain = NULL), values = -20:180)
leaflet() %>%
addProviderTiles("OpenStreetMap.Mapnik") %>%
setView(lat = 55, lng = -3, zoom = 6) %>%
addPolygons(data = UK,
stroke = FALSE, smoothFactor = 0.2, fillOpacity = 0.3,
fillColor = ~mypal(mydf$value),
popup = paste("Region: ", UK$NAME_2, "<br>",
"Value: ", mydf$value, "<br>")) %>%
addLegend(position = "bottomright", pal = mypal, values = mydf$value,
title = "UK value",
opacity = 1)
我想让传单调色板居中为零(红-白-绿发散)。我已经尝试了
我的代码
regions@data <- data.frame(region <- c("APAC (excl. China)", "Africa",
"Americas", "Europe", "Greater China", "Middle East"),
change_targeted <- c(36,-21,25,4,173,34))
color = "#666"
weight = 0.5
opacity = 1
fillOpacity = 1
dashArray = ""
hl_color = "black"
hl_weight = 1
hl_dashArray = ""
library(RColorBrewer)
nHalf = nrow(regions@data)/2
Min = min(regions@data[,"change_targeted"])
Max = max(regions@data[,"change_targeted"])
Thresh = 0
## Make vector of colors for values below threshold
rc1 = colorRampPalette(colors = c("red", "white"), space="Lab")(nHalf)
## Make vector of colors for values above threshold
rc2 = colorRampPalette(colors = c("white", "green"), space="Lab")(nHalf)
rampcols = c(rc1, rc2)
## In your example, this line sets the color for values between 49 and 51.
rampcols[c(nHalf, nHalf+1)] = rgb(t(col2rgb("white")), maxColorValue=256)
rb1 = seq(Min, Thresh, length.out=nHalf+1)
rb2 = seq(Thresh, Max, length.out=nHalf+1)[-1]
rampbreaks = c(rb1, rb2)
pal <- colorNumeric(
palette = rampcols, #"Blues", #YlGnBu,YlOrRd
domain = regions@data$change_targeted)
leaflet(regions, options = leafletOptions(zoomControl = FALSE,
attributionControl=FALSE)) %>%
addPolygons(color = color,
weight = weight, #smoothFactor = 0.5,
opacity = opacity, fillOpacity = fillOpacity,
dashArray = dashArray,
fillColor = ~pal(change_targeted),
highlightOptions = highlightOptions(color = hl_color,
weight = hl_weight,
dashArray = hl_dashArray,
bringToFront = TRUE),
label =
~as.character(paste0(region,"",round(change_targeted,1),"%")),
labelOptions = labelOptions(noHide = T, textOnly = F,
direction = "left",
textsize = "12px")) %>%
setView(35, 36, 0.5) %>%
addLegend("bottomright", pal = pal, values = ~change_targeted,
title = NULL,
labFormat = labelFormat(suffix = "%"), opacity=1)
我的地图
理想情况下,我希望只有非洲有红色,其余地区有白色到绿色的调色板
由于我没有你的数据、地区,我选择使用我一直在使用的虚拟数据来回答 Stack Overflow 上的一些问题。我希望你不介意。乔希的回答基本上给了你正确的方向。您可能误解了他的代码。在 that question 中,他创建并组合了两个调色板。然后,他手动将中点颜色设置为绿色。你想知道他在每个调色板中创建了 50 种颜色。你的故事是另一个故事;你需要扭曲他的回答。您想要使用红色、白色和绿色创建不对称的颜色范围。您需要创建介于红色和白色之间(即介于 -20 和 0 之间)的 20 种颜色,以及介于白色和绿色之间(即介于 0 和 180 之间)的 180 种颜色。您可以使用实际数据更改这些范围。
现在您想使用 Josh 的代码。您不必全部使用它。您所需要的只是创建两个调色板并将它们组合起来。完成后,您就可以开始了。在下面的代码中,我跳过了您的突出显示选项以尽量减少这种情况。
library(raster)
library(dplyr)
library(leaflet)
library(RColorBrewer)
### Get UK polygon data
UK <- getData("GADM", country = "GB", level = 2)
### Create dummy data
set.seed(111)
mydf <- data.frame(place = unique(UK$NAME_2),
value = sample(x = -20:180, size = n_distinct(UK$NAME_2), replace = TRUE))
### Create an asymmetric color range
## Make vector of colors for values smaller than 0 (20 colors)
rc1 <- colorRampPalette(colors = c("red", "white"), space = "Lab")(20)
## Make vector of colors for values larger than 0 (180 colors)
rc2 <- colorRampPalette(colors = c("white", "green"), space = "Lab")(180)
## Combine the two color palettes
rampcols <- c(rc1, rc2)
mypal <- colorNumeric(palette = rampcols, domain = mydf$value)
## If you want to preview the color range, run the following code
previewColors(colorNumeric(palette = rampcols, domain = NULL), values = -20:180)
leaflet() %>%
addProviderTiles("OpenStreetMap.Mapnik") %>%
setView(lat = 55, lng = -3, zoom = 6) %>%
addPolygons(data = UK,
stroke = FALSE, smoothFactor = 0.2, fillOpacity = 0.3,
fillColor = ~mypal(mydf$value),
popup = paste("Region: ", UK$NAME_2, "<br>",
"Value: ", mydf$value, "<br>")) %>%
addLegend(position = "bottomright", pal = mypal, values = mydf$value,
title = "UK value",
opacity = 1)