已知程序 import xarray as xr from collections import namedtuple import numpy as np from cartopy.mpl.ticker import LongitudeFormatter, LatitudeFormatter import matplotlib.ticker as mticker import cartopy.feature as cfeature import cartopy.crs as ccrs import matplotlib.pyplot as plt import matplotlib.cm as cm import matplotlib.colors as mcolors def region_mask(lon, lat, extents): lonmin, lonmax, latmin, latmax = extents return ( (lon >= lonmin) & (lon <= lonmax) & (lat >= latmin) & (lat <= latmax) ) Point = namedtuple('Point', ['x', 'y']) Pair = namedtuple('Pair', ['start', 'end']) time = '2023-05-04' filepath_DPR = r"C:\pythontest\zFactor\test1.nc4" extents = [110, 122, 25, 38] with xr.open_dataset(filepath_DPR) as f: lon_DPR = f['FS_Longitude'][:] lat_DPR = f['FS_Latitude'][:] zFactorFinalNearSurface = f['FS_SLV_zFactorFinalNearSurface'][:] nscan, nray = lon_DPR.shape midray = nray // 2 mask = region_mask(lon_DPR[:, midray], lat_DPR[:, midray], extents) index = np.s_[mask] lon_DPR = lon_DPR[index] lat_DPR = lat_DPR[index] zFactorFinalNearSurface = zFactorFinalNearSurface[index] for data in [ zFactorFinalNearSurface, ]: data.values[data <= -9999] = np.nan proj = ccrs.PlateCarree() fig = plt.figure(figsize=(10, 8)) ax = fig.add_subplot(111, projection=proj) ax.coastlines(resolution='50m', lw=0.5) ax.add_feature(cfeature.OCEAN.with_scale('50m')) ax.add_feature(cfeature.LAND.with_scale('50m')) ax.set_xticks(np.arange(-180, 181, 5), crs=proj) ax.set_yticks(np.arange(-90, 91, 5), crs=proj) ax.xaxis.set_minor_locator(mticker.AutoMinorLocator(2)) ax.yaxis.set_minor_locator(mticker.AutoMinorLocator(2)) ax.xaxis.set_major_formatter(LongitudeFormatter()) ax.yaxis.set_major_formatter(LatitudeFormatter()) ax.set_extent(extents, crs=proj) ax.tick_params(labelsize='large') def make_zF_cmap(levels): '''制作雷达反射率的colormap.''' nbin = len(levels) - 1 cmap = cm.get_cmap('jet', nbin) norm = mcolors.BoundaryNorm(levels, nbin) return cmap, norm levels_zF = [0, 1, 5, 10, 15, 20, 25, 30, 35, 40, 45] cmap_zF, norm_zF = make_zF_cmap(levels_zF) im = ax.contourf( lon_DPR, lat_DPR, zFactorFinalNearSurface, levels_zF, # 三个物理量为 (500, 49)就是在500*49的格点上赋予这三个物理量 cmap=cmap_zF, norm=norm_zF, extend='both', transform=proj ) cbar = fig.colorbar(im, ax=ax, ticks=levels_zF) cbar.set_label('zFactor (dBZ)', fontsize='large') cbar.ax.tick_params(labelsize='large') ax.set_title(f'DPR zFactor on {time}', fontsize='x-large') plt.show()如何将其中的zFactorFinal变量变为二维
时间: 2024-01-13 20:03:16 浏览: 369
基于python\numpy\pandas\xarray\matplotlib的气象数据处理、程序设程序设计及绘图
在这段代码中,zFactorFinalNearSurface的shape是(500, 49),其中第一维是nscan(扫描线数),第二维是nray(每个扫描线的射线数)。如果要将zFactorFinalNearSurface变为二维数组,可以将nscan和nray相乘得到总的格点数,然后使用reshape方法将其变为二维数组。代码如下:
```
zFactorFinalNearSurface = zFactorFinalNearSurface[index]
nscan, nray = zFactorFinalNearSurface.shape
zFactorFinalNearSurface_2d = zFactorFinalNearSurface.reshape(nscan*nray, 1)
```
其中,index是通过region_mask函数得到的布尔索引,用于筛选出位于指定区域内的数据。reshape方法中第一个参数是新的shape,这里是(nscan*nray, 1),表示将数据变成nscan*nray行,1列的形状。注意reshape方法返回的是一个新的数组,不会改变原始数组的值。
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