我有村里某些地点的坐标。每个坐标都意味着我在那里取样。进行研究后，我发现一个测试是阳性的，另一个是阴性的。我想在地图上显示它。该表有一列“注释”，其中包含从 1 到 5 的数字。根据值，点的颜色应该会发生变化。为此，我使用了以下公式
my.df <- read.table(text="
longitude latitude note name
75.317249 42.181918 5 D-01
75.316526 42.181163 5 D-01
75.317272 42.180741 1 N18AT01
75.317112 42.180024 5 D-01
75.317945 42.179996 5 D-01
75.318105 42.180327 5 D-01
75.318368 42.180437 5 D-01
75.318809 42.18116 5 D-01
75.319228 42.181068 1 N18AT02
75.320193 42.180452 5 D-01
75.320343 42.180352 1 N18AT03
75.320589 42.180272 1 N18AT04
75.322318 42.179844 1 N18AT05
75.323058 42.180092 5 D-01
75.323619 42.180545 1 N18AT06
75.323545 42.181142 1 N18AT07
75.323191 42.180965 5 D-01
75.322639 42.180886 1 N18AT08
75.321639 42.181038 4 N18AT09
75.321198 42.180693 5 D-01
75.321395 42.181233 5 D-01
75.3211 42.181462 1 N18AT10
75.319793 42.181997 4 N18AT11
75.318936 42.181964 5 D-01
75.32157 42.182443 1 N18AT12
75.322034 42.182258 3 D-01
75.322739 42.181873 5 D-01
75.32305 42.181991 1 N18AT13
75.324114 42.181683 2 N18AT14
75.324413 42.182389 1 N18AT15
75.324661 42.182426 5 D-01
75.325592 42.182185 4 N18AT16
75.326529 42.181774 5 D-01
75.32754 42.181101 4 N18AT17
75.327406 42.180947 5 D-01
75.326976 42.180899 1 N18AT18
75.327337 42.180554 5 D-03
75.327026 42.18008 3 N18AT19
75.327017 42.178938 1 N18AT20
75.326822 42.178524 2 N18AT21
75.327856 42.178314 5 D-01
75.328515 42.178022 1 N18AT22
75.32865 42.178548 4 N18AT23
75.329241 42.17802 5 D-01
75.330568 42.177277 4 N18AT24
75.333297 42.176426 1 N18AT25
75.334344 42.176361 5 D-01
75.335403 42.175511 3 N18AT26
75.336494 42.176149 5 D-01
75.336253 42.176882 1 N18AT27
75.336313 42.17767 5 D-03
75.335409 42.17839 1 N18AT28
75.332945 42.179434 5 D-01
75.331246 42.18019 1 N18AT29
75.329559 42.18017 2 N18AT30
75.32858 42.179969 1 N18AT31
75.32833 42.180402 5 D-01
75.32626 42.179303 1 N18AT32
75.325616 42.178956 5 D-01
75.324871 42.178909 4 N19AT33
75.319063 42.184572 1 N18AT34",
header=TRUE)
# Convert data frame to sf object
my.sf.point <- st_as_sf(x = my.df,
coords = c("longitude", "latitude"),
crs = "+proj=longlat +datum=WGS84 +ellps=WGS84 +clr=note")
# simple plot
plot(my.sf.point)
# interactive map:
library(mapview)
mapview(my.sf.point)```
As a result, dots appear on the map, but they have the same colour