结合ggplot、ggmap构建了如下图:
ggTun <- ggmap(TUN_map) +
geom_point( data = XY_EC_sf4326_df, aes(x = lon, y = lat), col="red",size = 2.5 ) +
geom_path( data = xyBord_Tunis4326_df,aes(x = lon, y = lat), linewidth = 1.0 ) +
xlab("Longitude (°E)") + ylab("Latitude (°S)" ) +
theme(axis.text.x = element_text(size = 20),axis.text.y = element_text(size = 20) ) +
theme(axis.title.x = element_text(size = 26),axis.title.y = element_text(size = 26) ) +
theme(legend.title=element_text(size=15),legend.text=element_text(size=15),legend.position = c(0.93, 0.13)) + scale_color_gradientn(colours = c('#5749a0', '#0f7ab0', '#00bbb1',
'#bef0b0', '#fdf4af', '#f9b64b',
'#ec840e', '#ca443d', '#a51a49'))
并使用 ggsn 添加比例尺
test0 <- ggTun + ggsn::scalebar(x.min = leftTun+0.015, x.max = rightTun,
y.min = bottomTun+0.015, y.max = topTun,
model = "WGS84", dist_unit = "km", transform = TRUE,
location = "bottomleft", height = 0.015, dist = 2,
st.size = 3, border.size = 0.8)
但是,当我尝试使用以下命令添加指北针时:
test1 <- test0 + ggsn::north(x.min = leftTun+0.015, x.max = rightTun,
y.min = bottomTun+0.015, y.max = topTun, scale = 1.5)
我收到以下错误:
我注意到“annotation_custom”问题,但我没有找到解决它的方法。非常感谢任何帮助。