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AndyC1000

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Python if statement exclude "--" values

Dear all,

I'm reading data from a netcdf file, I've noticed some fields are written to my file as "--".

When I print the row to the console its value is:
[-33.939999, 151.03918, masked, masked, masked, masked, masked, masked, masked]

I've tried the below code block to check if the row doesn't contain masked or "--" and write those values.  Its not working!

How do I exclude or check for those values?

Thanks

if "masked" not in content:
   outputwriter.writerow(content)
   print content

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pepr

The question is not clear. There is not enough information to answer. Please, show some example.
Avatar of AndyC1000

ASKER

Admin, I have provided a response at http:Q_28627100.html

To clarify this question the below code block writes a csv file.   My issue is when there is no data in the content string for a lat/lon, the row is outputted to the csv file as

[-33.939999, 151.03918, --, --, --, --, --, --, --]

or to the console as

[-33.939999, 151.03918, masked, masked, masked, masked, masked, masked, masked]

I tried wrapping the outputwriter around  an if statement i.e.

if "masked" not in content:
   outputwriter.writerow(content)
   print content

with open(r'C:/output.csv', 'wb') as csvFile:
    outputwriter = csv.writer(csvFile, delimiter=',')
    for date_val in date_strings:
        header.append(date_val)
    outputwriter.writerow(header)
    for lat_index, lat in enumerate(lats):
        for lon_index, lon in enumerate(lons):
            content = [lat,lon]
            for time_index, time in enumerate(times[:]): 
                data = value[time_index,lat_index,lon_index]
                content.append(data)
            outputwriter.writerow(content) 

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please post a sample file
from netCDF4 import Dataset, num2date
import csv

filename = "C:/Test.nc"

nc = Dataset(filename, 'r', Format='NETCDF4')

# get coordinates variables
lats = nc.variables['latitude'][:] 
lons = nc.variables['longitude'][:]

if nc.variables['latitude'].units != 'degrees_north':
    raise AttributeError('latitude units attribute not what was expected')

if nc.variables['longitude'].units != 'degrees_east':
    raise AttributeError('longitude units attribute not what was expected')

val = nc.variables['Min_SFC'][:]

times = nc.variables['time']
dates = num2date(times[:],times.units)
date_strings = [date.strftime('%d-%m-%Y') for date in dates]

header =  ['Latitude', 'Longitude']

with open(r'C:/output.csv', 'wb') as csvFile:
    outputwriter = csv.writer(csvFile, delimiter=',')
    for date_val in date_strings:
        header.append(date_val)
    outputwriter.writerow(header)
    for lat_index, lat in enumerate(lats):
        for lon_index, lon in enumerate(lons):
            content = [lat,lon]
            for time_index, time in enumerate(times[:]): 
                data = val[time_index,lat_index,lon_index]
                content.append(data)
            #outputwriter.writerow(content) 
            if "masked" not in content:
                outputwriter.writerow(content)
                print content

# close netcdf 
nc.close()

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Please a sample DATA file.  Sorry for the confusion.
Attached is the output data file, I'm not able to post the input data file (netcdf).
Output.csv
This will filter the csv file.  It is crude, but it does seem to work.  Of course, you would replace the print statement with a file-writing statement.
    import csv

    filename = "C:\Users\aikimark\Downloads\Output.csv"
    csvfile= open(filename, 'r')
    f=csv.reader(csvfile)
    for line in f:
        disposition = "drop"
        for item in line[2:]:
            if item <> "--":
                disposition = "keep"
                break
                
        print disposition, line

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ASKER CERTIFIED SOLUTION
Avatar of aikimark
aikimark
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