---
title: "Maps"
author: "Prof. Eric A. Suess"
format:
  html:
    self-contained: true
---


```{r}
library(pacman)

p_load(tidyverse, nasaweather)

atmos	                       # Atmospheric data.
borders <- ungroup(borders)	 # Country borders, ungroup fixes a problem 
elev	                       # Elevation.
glaciers                     # Glacier locations
storms	                     # Storm tracks data

```


```{r}
p <- storms  |>  ggplot(aes(y = wind, x = pressure, color = type)) +
  geom_point(alpha = 0.3) 

p

p + geom_smooth()
```


All storms

Determine the part of the map to plot the storm paths on.  Compute the minimum and maximum values of the latitude and longitude.

```{r}
bbox <- storms |> 
  select(lat, long) |> 
  map_df(range)          # using the purrr R package

bbox
```

```{r}
base_map <- map_data("world") |>  ggplot( aes(x = long, y = lat)) +
  geom_path(aes(group = group), color = "black", size = 0.1) +
  lims(x = bbox$long, y = bbox$lat)

base_map <- base_map + geom_path(data = storms, aes(color = name, alpha = 0.01, size = wind),
                     arrow = arrow(length = unit(0.005, "inches"))) +
  facet_wrap(~year)

base_map

base_map + theme(legend.position = "none")
```

Show the legend.

```{r}
legend <- cowplot::get_legend(base_map)

cowplot::plot_grid(legend, scale = .5)
```

Only Tropical Storms

```{r}
base_map <- map_data("world")  |>  ggplot(aes(x = long, y = lat)) +
  geom_path(aes(group = group), color = "black", size = 0.1) +
  lims(x = bbox$long, y = bbox$lat)

base_map

storms2 <- storms  |>  filter(type == "Tropical Storm") 

base_map + geom_path(data = storms2, aes(color = name, alpha = 0.01, size = wind), arrow = arrow(length = unit(0.005, "inches"))) +
  facet_wrap(~year) +
  theme(legend.position = "none")

```


Some futher maps

```{r}
library(maps)

state <- map_data("state")
county <- map_data("county")
usa <- map_data("usa")
world <- map_data("world")
```

states

```{r}
state
```

```{r}
gg <- ggplot()
gg <- gg + geom_map(data=state, map=state,
                     aes(long, lat, map_id=region),
                     color="#2b2b2b", fill=NA, size=0.15)
gg
```


```{r}
gg <- ggplot()
gg <- gg + geom_map(data=county, map=county,
                     aes(long, lat, map_id=region),
                     color="#2b2b2b", fill=NA, size=0.15)
gg

gg <- ggplot()
gg <- gg + geom_map(data=state, map=state,
                     aes(long, lat, map_id=region),
                     color="#2b2b2b", fill=NA, size=0.15)
gg

gg <- ggplot()
gg <- gg + geom_map(data=usa, map=usa,
                     aes(long, lat, map_id=region),
                     color="#2b2b2b", fill=NA, size=0.15)
gg
```

```{r}
ggplot() + borders("county", c("washington", "california","texas"))
```