将正方形或三角形标记（不是圆形）添加到 R 绘图地图

Question

我可以像这个例子一样在地图上绘制圆形标记。但是我想在 add_markers 中将标记形状从圆形更改为正方形，但是在帮助（add_markers）或在线示例中找不到解决方案。我试图添加 type=list("squares") 但不幸的是它没有改变任何东西。

require(plotly)

df<- read.csv('https://raw.githubusercontent.com/plotly/datasets/master/2014_ebola.csv')
# restrict from June to September
df <- subset(df, Month %in% 6:9)
# ordered factor variable with month abbreviations
df$abbrev <- ordered(month.abb[df$Month], levels = month.abb[6:9])
# September totals
df9 <- subset(df, Month == 9)

p <- df %>%
  plot_geo(
    locationmode = 'country names', sizes = c(1, 600), color = I("black")
  ) %>%
  add_markers(
    y = ~Lat, x = ~Lon, locations = ~Country,
    size = ~Value, color = ~abbrev, text = ~paste(Value, "cases")
  ) 
p

Answer 1

有一个参数叫symbol。你可以使用

p <- df %>%
  plot_geo(
    locationmode = 'country names', sizes = c(1, 600), color = I("black")
  ) %>%
  add_markers(
    y = ~Lat, x = ~Lon, locations = ~Country,
    size = ~Value, color = ~abbrev, text = ~paste(Value, "cases"),
    symbol = ~abbrev
  ) 
p

你也可以指定符号，使用

p <- df %>%
  plot_geo(
    locationmode = 'country names', sizes = c(1, 600), color = I("black")
  ) %>%
  add_markers(
    y = ~Lat, x = ~Lon, locations = ~Country,
    size = ~Value, color = ~abbrev, text = ~paste(Value, "cases"),
    symbol = ~abbrev, symbols = c('circle', 'square', 'x', 'triangle')
  ) 
p

如果您只想将圆圈切换为另一个符号，请使用：

p <- df %>%
  plot_geo(
    locationmode = 'country names', sizes = c(1, 600), color = I("black")
  ) %>%
  add_markers(
    y = ~Lat, x = ~Lon, locations = ~Country,
    size = ~Value, color = ~abbrev, text = ~paste(Value, "cases"),
    symbol = 'triangle'
  ) 
p

希望对你有帮助。