嘿伙计，

最近有人问我如何可视化与R的航班联系，所以我决定撰写一篇博客文章，其中包含有关该主题的简短教程：目的是绘制从NYC JFK机场到美国其他主要机场的所有可能的航班联系。为此，我们将使用以下软件包：

• nycflights13: 2013年从纽约出发的航班的数据集。
• dplyr: 用于处理数据集的软件包。
• 地图: 映射包。
• geosphere: 球面三角测量软件包。

Make sure to install and load these beforehand using the install.packages() and library() functions.

数据：

Lets get  a quick overview on the 数据set first. Once you loaded the package nycflights13 you have access to the 数据set airports:

library(nycflights13)
airports
Source: local 数据 frame [1,397 x 7]

   faa                           name      lat        lon  alt tz dst
1  04G              Lansdowne Airport 41.13047  -80.61958 1044 -5   A
2  06A  Moton Field Municipal Airport 32.46057  -85.68003  264 -5   A
3  06C            Schaumburg Regional 41.98934  -88.10124  801 -6   A
4  06N                Randall Airport 41.43191  -74.39156  523 -5   A
5  09J          Jekyll Island Airport 31.07447  -81.42778   11 -4   A
6  0A9 Elizabethton Municipal Airport 36.37122  -82.17342 1593 -4   A
7  0G6        Williams County Airport 41.46731  -84.50678  730 -5   A
8  0G7  Finger Lakes Regional Airport 42.88356  -76.78123  492 -5   A
9  0P2   Shoestring Aviation Airfield 39.79482  -76.64719 1000 -5   U
10 0S9          Jefferson County Intl 48.05381 -122.81064  108 -8   A
.. ...                            ...      ...        ...  ... .. ...

The 数据set contains useful metadata on airports. For our map however we only want airports that are located in the US. Therefore we will make a couple of 数据 filtering steps using the dplyr package. We will select only those airports which have a latitude <48.5和经度>-130。然后，我们将从此数据集中排除肯尼迪国际机场，并创建一个仅包含肯尼迪国际机场的新数据框：

usairports <- filter(airports, lat < 48.5)
usairports <- filter(usairports, lon > -130)
usairports <- filter(usairports, faa!="JFK") #filter out jfk
jfk <- filter(airports, faa=="JFK") #separate df for jfk

创建航班转机地图：

The 数据 is now prepared for our final flight connection map. The first step will be to create a basemap for the US using the 地图 package:

#create basemap
map("world", regions=c("usa"), fill=T, col="grey8", bg="grey15", ylim=c(21.0,50.0), xlim=c(-130.0,-65.0))
#overlay airports
points(usairports$lon,usairports$lat, pch=3, cex=0.1, col="chocolate1")

现在，地图应如下所示：

The next and final step is to add the flight connectins from NYC to all other airports using the gesophere package and the gcIntermediate() function.

为（i in（1：dim（usairports [[1]）））{ 
inter <-gcIntermediate（c（jfk $ lon [1]，jfk $ lat [1]），c（usairports $ lon [i]，usairports $ lat [i]），n = 200）
行数（inter，lwd = 0.1，col ="绿松石2")    
}

The gcIntermediate() function takes two points and creates a circular connection between them. With the lines() function you add this circle to the plot. In this example this is done for all airports in the 数据frame with a for loop. The final map can be seen below:

享受最终结果！如果您对dplyr或gesophere软件包有任何疑问，请随时提问。

干杯

马丁