matplotlib_pyplot_BARBS.py

import cartopy.crs as ccrs
import cartopy.feature as cfeature
import matplotlib.path as mpath
import matplotlib.pyplot as plt
import numpy as np
import xarray as xr
from cartopy.io.shapereader import Reader

plt.rcParams['font.sans-serif'] = ['SimHei']  ###防止无法显示中文并设置黑体
air_hgt_500 = xr.open_dataset('D:\\python\\tianzhen\\shixi2\\all.nc')
lat = air_hgt_500['lat'][:]
lon = air_hgt_500['lon'][:]
# lats = air_hgt_500.lat.data
# lons = air_hgt_500.lon.data
lons, lats = np.meshgrid(lon, lat)

###################################地图设置##########################
leftlon, rightlon, lowerlat, upperlat = (50, 160, 10, 80)
fig = plt.figure(figsize=(9, 6))  # 画布大小
ax = fig.subplots(1, 1, subplot_kw={'projection': ccrs.LambertConformal(central_longitude=105, central_latitude=30)})

path = mpath.Path([[leftlon, lowerlat], [rightlon, lowerlat], [rightlon, upperlat], [leftlon, upperlat],
                   [leftlon, lowerlat]]).interpolated(20)  ###设置地图边界
transpath = (ccrs.PlateCarree()._as_mpl_transform(ax) - ax.transData).transform_path(path)

ax.set_extent([50, 160, 10 - 10, 80])  ## 调整图片大小在画布中
ax.set_boundary(transpath)
ax.add_feature(cfeature.COASTLINE.with_scale('110m'))
ax.gridlines(draw_labels=True, x_inline=False, y_inline=False)
ax.add_geometries(Reader('D:\\maplist\\China_province\\bou2_4l.shp').geometries(), ccrs.PlateCarree(),
                  facecolor='none', edgecolor='gray', linewidth=0.8)  ###添加省界
#####################################
uwind = np.zeros((29, 45))
vwind = np.zeros((29, 45))
plot_air_500 = air_hgt_500['air'][0, 5, :, :]
plot_hgt_500 = air_hgt_500['hgt'][0, 5, :, :]
uwind[:, :] = air_hgt_500['u'][0, 5, :, :]
vwind[:, :] = air_hgt_500['v'][0, 5, :, :]

air_levels = np.arange(-100, 20, 4)  # 设置等值线间隔
hgt_levels = np.arange(400, 600, 4)
#############画等值线图##################
denghgtlines = ax.contour(lon, lat, plot_hgt_500, levels=hgt_levels,
                          colors='mediumblue', linewidths=0.8, transform=ccrs.PlateCarree())
plt.clabel(denghgtlines, inline=True, fontsize=8, fmt='%.0f')

dengairlines = ax.contour(lon, lat, plot_air_500, levels=air_levels,
                          colors='red', linewidths=0.8, linestyles='-', transform=ccrs.PlateCarree())
plt.clabel(dengairlines, inline=True, fontsize=8, fmt='%.0f')
#############https://matplotlib.org/stable/api/_as_gen/matplotlib.pyplot.contour.html#matplotlib.pyplot.contour

######################################################画风羽图##################################################
wind_slice = (slice(None, None, 3), slice(None, None, 3))  ####调风羽的密度
plt.barbs(lons[wind_slice], lats[wind_slice], uwind[wind_slice], vwind[wind_slice], pivot='middle', length=4,
          color='black', transform=ccrs.PlateCarree())
#########[x,y,u,v]  这四个都要 ndarray 形式
######### https://matplotlib.org/stable/api/_as_gen/matplotlib.pyplot.barbs.html#matplotlib.pyplot.barbs
ax.set_title('2021-05-20 00 时 500hPa 温压场', fontsize=12)

gl = ax.gridlines()  ##生成网格线
ax.grid()
plt.show()
fig.savefig('d:\\python\\hh')