add_rasterly: Add "rasterly" trace to a Plotly visualization

In rasterly: Easily and Rapidly Generate Raster Image Data with Support for 'Plotly.js'

Description

Add trace to a Plotly visualization.

Usage

add_rasterly_heatmap(
  p,
  x = NULL,
  y = NULL,
  z = NULL,
  ...,
  data = NULL,
  inherit = TRUE,
  on = NULL,
  size = NULL,
  scaling = NULL
)

add_rasterly_image(
  p,
  x = NULL,
  y = NULL,
  z = NULL,
  ...,
  data = NULL,
  inherit = TRUE,
  color = NULL,
  on = NULL,
  size = NULL
)

Arguments

p	A plotly object
x	Numeric vector or expression. The x variable, to be passed on to aes().
y	Numeric or expression. The y variable, to be passed on to aes().
z	Numeric. A numeric matrix (optional), to be processed with add_heatmap.
...	Arguments (i.e., attributes) passed along to the trace type or rasterly.
data	A data.frame or SharedData object (optional).
inherit	Logical. Inherit attributes from plotly?
on	Numeric vector or expression. Provides the data on which to reduce, to be passed on to aes().
size	Numeric vector or expression. Pixel size for each observation, to be passed on to aes().
scaling	Character string or function. The scaling method to be used for the trace.
color	Numeric vector or expression. Pixel color for each observation, to be passed on to aes().

Examples

## Not run: 
if(requireNamespace("plotly") && requireNamespace("data.table") &&
  requireNamespace("lubridate")) {
 # Load data
 url1 <- "https://raw.githubusercontent.com/plotly/datasets/master/uber-rides-data1.csv"
 ridesRaw_1 <-  url1 %>%
   data.table::fread(stringsAsFactors = FALSE)
 url2 <- "https://raw.githubusercontent.com/plotly/datasets/master/uber-rides-data2.csv"
 ridesRaw_2 <-  url2 %>%
   data.table::fread(stringsAsFactors = FALSE)
 url3 <- "https://raw.githubusercontent.com/plotly/datasets/master/uber-rides-data3.csv"
 ridesRaw_3 <-  url3 %>%
   data.table::fread(stringsAsFactors = FALSE) 
 ridesDf <- list(ridesRaw_1, ridesRaw_2, ridesRaw_3) %>% 
   data.table::rbindlist()
 time <- lubridate::ymd_hms(ridesDf$`Date/Time`)
 ridesDf <-  ridesDf[, 'Date/Time':=NULL][, list(Lat, 
                                                 Lon,
                                                 hour = lubridate::hour(time),
                                                 month = lubridate::month(time),
                                                 day = lubridate::day(time))]
 ############################# add_rasterly_heatmap #############################
 #### quick start
 p <- plot_ly(data = ridesDf) %>%
        add_rasterly_heatmap(x = ~Lat, y = ~Lon)
 p
 #### set artificial scaling function
 zeroOneTransform <- function(z) {
   minz <- min(z)
   maxz <- max(z)
   M <- matrix((z - minz)/(maxz - minz), nrow = dim(z)[1])
   return(M)
 }
 plot_ly(data = ridesDf) %>%
   add_rasterly_heatmap(x = ~Lat,
                y = ~Lon,
                on = ~-Lat,
                reduction_func = "max",
                scaling = zeroOneTransform) %>%
   plotly::layout(
     xaxis = list(
       title = "x"
     ),
     yaxis = list(
       title = "y"
     )
   )
 ############################# add_rasterly_image #############################
 p <- plot_ly(data = ridesDf) %>%
        add_rasterly_image(x = ~Lat, y = ~Lon, color = ~hour,
                           # even `color_map` is deprecated,
                           # it is still a good way to specify the color mapping
                           color_map = hourColors_map, 
                           plot_width = 400, plot_height = 400)
 p
 }

## End(Not run)

rasterly documentation built on July 2, 2020, 2:12 a.m.