NetCDF Longitude values shift

anTonialcaraz — Sat, 11 Dec 2021 14:44:16 GMT

Hi,

I've been several days with this not quite getting what I need. Any help would be much appreciated.

I'm trying to use python to shift the longitude values of a netcdf file. The original file longitude goes from -1.875 to +360

I need the file to show properly when importing it in Arcmap (Make NetCDF Raster Layer) so the raster and its values are -180 180 (as well as -90 90). The values are vertical velocity depth.

I'm trying a short script that someone showed online with a similar issue. Apparently it worked for him. In my case I just manage to shift the frame but not the values (see picture).

Any suggestions? Many thanks

import arcpy
import numpy as np
import netCDF4
from netCDF4 import Dataset
from arcpy import env
arcpy.env.overwriteOutput=True
from arcpy.sa import*
arcpy.CheckOutExtension("Spatial")


Bathy = Dataset(r"H:\NETcdf_TEST\tdhteo.pfclapr.nc",'r+', format="NETCDF4")

lon = Bathy.variables[u'longitude'][:]
lat = Bathy.variables[u'latitude'][:]
depth = Bathy.variables[u'W_mm_dpth'][:]

depth_new = np.roll(depth, 360, axis = 1)
lon_new = lon[:]-178.125

Bathy.variables[u'longitude'][:] = lon_new
Bathy.variables[u'W_mm_dpth'][:] = depth_new
Bathy.close()
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Re: NetCDF Longitude values shift

anTonialcaraz — Tue, 03 Jul 2018 10:20:27 GMT

This does the job. Thanks

depth_new = np.roll(depth, 720, axis = 3)‍

topic Re: NetCDF Longitude values shift in Python Questions

NetCDF Longitude values shift

Re: NetCDF Longitude values shift