[Numpy-discussion] mask one array using another array

questions anon questions.anon at gmail.com
Mon Nov 21 20:36:43 EST 2011


Excellent, thank you.
I just realised this does not work with my data because of the extra
dimension.
I have a mask that matches my 2-dimensional array but my data is for every
hour over a month so the arrays do not match. Is there a way to make them
match or mask each time?
thanks again

This is some of my code:


                        for ncfile in files:
                                if ncfile[-3:]=='.nc':
                                    print "dealing with ncfiles:",
path+ncfile
                                    ncfile=os.path.join(path,ncfile)
                                    ncfile=Dataset(ncfile, 'r+', 'NETCDF4')
                                    TSFC=ncfile.variables['T_SFC'][:]
                                    TIME=ncfile.variables['time'][:]

fillvalue=ncfile.variables['T_SFC']._FillValue
                                    TSFC=MA.masked_values(TSFC, fillvalue)
                                    ncfile.close()

                                    TSFC=MA.masked_array(TSFC,
mask=newmask.mask)





On Tue, Nov 22, 2011 at 11:21 AM, Olivier Delalleau <shish at keba.be> wrote:

> If your new array is x, you can use:
>
> numpy.ma.masked_array(x, mask=mask.mask)
>
> -=- Olivier
>
> 2011/11/21 questions anon <questions.anon at gmail.com>
>
>> I am trying to mask one array using another array.
>>
>> I have created a masked array using
>> mask=MA.masked_equal(myarray,
>> 0),
>> that looks something like:
>> [1  -  -  1,
>>  1  1  -  1,
>>  1  1  1  1,
>>  -   1  -  1]
>>
>> I have an array of values that I want to mask whereever my mask has a a
>> '-'.
>> how do I do this?
>> I have looked at
>> http://www.cawcr.gov.au/bmrc/climdyn/staff/lih/pubs/docs/masks.pdf but
>> the command:
>>
>> d = array(a, mask=c.mask()
>>
>> results in this error:
>> TypeError: 'numpy.ndarray' object is not callable
>>
>> I basically want to do exactly what that article does in that equation.
>>
>> Any feedback will be greatly appreciated.
>>
>> _______________________________________________
>> NumPy-Discussion mailing list
>> NumPy-Discussion at scipy.org
>> http://mail.scipy.org/mailman/listinfo/numpy-discussion
>>
>>
>
> _______________________________________________
> NumPy-Discussion mailing list
> NumPy-Discussion at scipy.org
> http://mail.scipy.org/mailman/listinfo/numpy-discussion
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/numpy-discussion/attachments/20111122/a640aa5b/attachment.html>


More information about the NumPy-Discussion mailing list