选取数据
PRD.fields 存放逐层雷达体扫数据，每一层是一个 xarray.Dataset。
最推荐的访问方式
from pycwr.io import read_auto
radar = read_auto("./data/file.bin.bz2")
print(radar.fields[0])
print(radar.get_sweep_field(0, "dBZ"))
按层索引
sweep0 = radar.fields[0]
dBZ0 = radar.fields[0]["dBZ"]
更推荐显式走：
dBZ0 = radar.get_sweep_field(0, "dBZ", range_mode="aligned")
dBZ0_native = radar.get_sweep_field(0, "dBZ", range_mode="native")
scan_info
scan_info 存放站点和扫描方式信息，例如：
latitude
longitude
altitude
scan_type
frequency
start_time
end_time
nyquist_velocity
unambiguous_range
rays_per_sweep
fixed_angle
字段关键词
表 1 给出当前常见字段和变量含义：
key |
variable |
|---|---|
dBT |
total_power |
dBZ |
reflectivity |
V |
velocity |
W |
spectrum_width |
ZDR |
differential_reflectivity |
CC |
cross_correlation_ratio |
PhiDP |
differential_phase |
KDP |
specific_differential_phase |
HCL |
hydro_class |
CF |
clutter_flag |
Zc |
corrected_reflectivity |
Vc |
corrected_velocity |
Wc |
spectrum_width_corrected |
ZDRc |
corrected_differential_reflectivity |
KDPc |
corrected_specific_differential_phase |
SNRH |
horizontal_signal_noise_ratio |
SNRV |
vertical_signal_noise_ratio |
注意
dBZ/Zc、V/Vc、W/Wc、ZDR/ZDRc 都是独立变量
corrected 字段不是对原始字段的原地覆盖
需要排序后的方位视图时，可用 sort_by_azimuth=True