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Code takes a netCDF4 file and converts the data to GeoTiff:

import numpy as np, sys
from osgeo import gdal
from osgeo import osr
import netCDF4


f=netCDF4.Dataset("mydata.nc")

time = f.variables["time"]
lon = f.variables["lon"]
lat = f.variables["lat"]
data = f.variables["data"]
dims = f.dimensions
xsize = len(dims['lon'])
ysize = len(dims['lat'])

lonarray = np.array(lon)
latarray = np.array(lat)
dataarray = np.array(data)

# get bounds
xmin,ymin,xmax,ymax = [lonarray.min(),latarray.min(),lonarray.max(),latarray.max()]

# no. rows and columns
nrows,ncols = np.shape(dataarray)

# resolution of x/y
xres = (xmax-xmin)/float(ncols)
yres = (ymax-ymin)/float(nrows)

geot=(xmin,xres,0,ymax,0, -yres)

output_raster = gdal.GetDriverByName('GTiff').Create('myraster.tif',ncols,
nrows, 1 ,gdal.GDT_CInt16, options = ['PHOTOMETRIC=MINISWHITE'])  # Open the file

output_raster.SetGeoTransform(geot)            # Specify its coordinates

srs = osr.SpatialReference()                           # Establish its coordinate encoding

srs.ImportFromEPSG(4326)                               # This one specifies WGS84 lat long.

output_raster.SetProjection(srs.ExportToWkt())         # Exports the coordinate system
                                                       # to the file
output_raster.GetRasterBand(1).WriteArray(dataarray)   # Writes my array to the raster

output_raster.FlushCache()

del output_raster

After I load the Geotif into Arc Globe, the min value is black, ie. the ['PHOTOMETRIC=MINISWHITE'] tag has not done what I expected.

1

I solved this by writing a function to invert my data.

def invert_dataset(min, max, data):

for i, row in enumerate(data):
    for j, value in enumerate(row):
        A = value - min
        inverted_value = max - A
        data[i][j] = inverted_value
return data

I didn't use PIL as it returned an error when trying to open my tiff image.

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