用聚类标记制作传单地图。markerClusterOptions（）中是否有一个参数可根据缩放级别控制组数？例如，在默认缩放下，我的地图仅显示1800个观测值的3个群集。但是，如果在默认缩放下至少有两倍的群集，那将是很好的。
我不想使用freezeAtZoom，因为这样用户将无法放大并看到每个观察结果。
数据来自：https : //data.sccgov.org/Public-Safety/Crime-Reports/n9u6-aijz/data
library(tidyverse);library(leaflet);library(lubridate)
crime_reports <- read_csv("Crime_Reports.csv")
car_burglaries <- crime_reports %>% filter(incident_type_primary=="VEHICLE BURGLARY") %>%
mutate(datetime=mdy_hms(incident_datetime)) %>%
arrange(datetime)
leaflet(car_burglaries) %>% addTiles() %>%
addMarkers(
popup = ~paste(as.character(incident_datetime),",","Case number",as.character(case_number)),
label = ~as.character(address_1),
clusterOptions = markerClusterOptions()
)
如何将色阶从默认的紫色更改为黄色？我尝试向 add_trace() 添加颜色和色阶参数，但它引发了错误。
具有默认颜色的可重现代码：
library(plotly); library(reshape2); library(tidyverse)
sleep <- read.table("http://www.statsci.org/data/general/sleep.txt", header=T)
sleep <- na.omit(sleep)
sleep <- mutate(sleep, logTotalSleep = log(TotalSleep))
sleep_mod <- lm(logTotalSleep ~ Gestation + Danger, data=sleep)
# Graph Resolution (more important for more complex shapes)
graph_reso <- 0.5 #0.05
# Setup Axis
axis_x <- seq(min(sleep$Gestation), max(sleep$Gestation), by = graph_reso)
axis_y <- seq(min(sleep$Danger), max(sleep$Danger), by = graph_reso)
# Sample points
sleep_surface <- expand.grid(Gestation = axis_x,
Danger = axis_y,
KEEP.OUT.ATTRS = F)
sleep_surface$TotalSleep <- exp(predict.lm(sleep_mod, newdata = sleep_surface)) # exp …伪SQL:
SELECT *
FROM table
WHERE(if var1=a then var2 must=b)
AND (if var2=c then var3 must=d);
该查询将返回与条件匹配的var1 = a和var2 = b的两行,以及var1!= a和var2!= c的所有行.
不使用IF,使用OR将忽略其中一个条件,并使用AND将强制执行每一行的所有条件.