在Visual Studio Code中利用python3 matplotlib繪製等值線圖

配置Python開發環境

安裝python

記得勾選添加環境變量。Add Python to PATH

import this

欣賞下python之禪

下載安裝第三方包

pip install flake8
pip install yapf

檢查是否已存在需要的包

pip list

配置Visual Studio Code

用戶設置

Visual Studio Code 文件 -> 首選項 -> 設置 -> 用戶 配置settings.json

"python.pythonPath": "python3",

工作區域設置

在工作區域輸入以下內容：

{
    "python.linting.flake8Enabled": true,
    "python.formatting.provider": "yapf",
    "python.linting.flake8Args": ["--max-line-length=248"],
    "python.linting.pylintEnabled": false
}

matplotlib

安裝matplotlib

python -m pip install matplotlib

測試運行matplotlib

運行測試程序：

import numpy as np
from matplotlib import pyplot as plt

x = np.arange(1, 11)
y = 2 * x + 5
plt.title("Matplotlib demo")
plt.xlabel("x axis caption")
plt.ylabel("y axis caption")
plt.plot(x, y)
plt.show()

basemap

安裝geos

pip install geos

安裝basemap

basemap無法用pip安裝

訪問 https://www.lfd.uci.edu/~gohlke/pythonlibs/

選擇basemap，根據自己安裝的Python版本選擇，32和64是指安裝的Python的版本，cp後面的數字是Python的版本。

還需在當前頁面下載pyproj，pyhdf，netCDF4對應的whl包

pip install pyproj-2.4.0-cp37-cp37m-win_amd64.whl
pip install pyhdf-0.10.1-cp37-cp37m-win_amd64.whl
pip install basemap-1.2.1-cp37-cp37m-win_amd64.whl
pip install netCDF4-1.5.3-cp37-cp37m-win_amd64.whl

測試運行basemap

運行測試程序：

import matplotlib.pyplot as plt
from mpl_toolkits.basemap import Basemap
plt.figure(figsize=(16, 8))
m = Basemap()
m.drawcoastlines()
m.drawcountries(linewidth=1.5)
plt.show()

運行

參考 https://matplotlib.org/basemap/users/examples.html

我們使用第一個例子：Plot contour lines on a basemap（在地圖上畫輪廓線）

from mpl_toolkits.basemap import Basemap
import matplotlib.pyplot as plt
import numpy as np
# set up orthographic map projection with
# perspective of satellite looking down at 50N, 100W.
# use low resolution coastlines.
map = Basemap(projection='ortho',lat_0=45,lon_0=-100,resolution='l')
# draw coastlines, country boundaries, fill continents.
map.drawcoastlines(linewidth=0.25)
map.drawcountries(linewidth=0.25)
map.fillcontinents(color='coral',lake_color='aqua')
# draw the edge of the map projection region (the projection limb)
map.drawmapboundary(fill_color='aqua')
# draw lat/lon grid lines every 30 degrees.
map.drawmeridians(np.arange(0,360,30))
map.drawparallels(np.arange(-90,90,30))
# make up some data on a regular lat/lon grid.
nlats = 73; nlons = 145; delta = 2.*np.pi/(nlons-1)
lats = (0.5*np.pi-delta*np.indices((nlats,nlons))[0,:,:])
lons = (delta*np.indices((nlats,nlons))[1,:,:])
wave = 0.75*(np.sin(2.*lats)**8*np.cos(4.*lons))
mean = 0.5*np.cos(2.*lats)*((np.sin(2.*lats))**2 + 2.)
# compute native map projection coordinates of lat/lon grid.
x, y = map(lons*180./np.pi, lats*180./np.pi)
# contour data over the map.
cs = map.contour(x,y,wave+mean,15,linewidths=1.5)
plt.title('contour lines over filled continent background')
plt.show()