On 07.12.2011, at 5:07AM, Olivier Delalleau wrote:
> I *think* it may work better if you replace the last 3 lines in your loop by:
>
> a=all_TSFC[0]
> if len(all_TSFC) > 1:
> N.maximum(a, TSFC, out=a)
>
> Not 100% sure that would work though, as I'm not entirely confident I
> understand your code.
>
> -=- Olivier
>
> 2011/12/6 questions anon <questions.a...@gmail.com>
> Something fancier I think,
> I am able to compare the result with my previous method so I can easily see I
> am doing something wrong.
> see code below:
>
>
> all_TSFC=[]
> for (path, dirs, files) in os.walk(MainFolder):
> for dir in dirs:
> print dir
> path=path+'/'
> for ncfile in files:
> if ncfile[-3:]=='.nc':
> print "dealing with ncfiles:", ncfile
> ncfile=os.path.join(path,ncfile)
> ncfile=Dataset(ncfile, 'r+', 'NETCDF4')
> TSFC=ncfile.variables['T_SFC'][:]
> fillvalue=ncfile.variables['T_SFC']._FillValue
> TSFC=MA.masked_values(TSFC, fillvalue)
> ncfile.close()
> all_TSFC.append(TSFC)
> a=TSFC[0]
> for b in TSFC[1:]:
> N.maximum(a,b,out=a)
>
I also understood TSFC is already the array you want to work on, so above
you'd just take a slice and overwrite the result in the next file iteration
anyway.
Iterating over the list all_TSFC should be correct, but I understood you
don't want to load the entire input into memory in you working code.
Then you can simply skip the list, just need to take care of initial conditions
-
something like the following should do:
path=path+'/'
a = None
for ncfile in files:
if ncfile[-3:]=='.nc':
print "dealing with ncfiles:", ncfile
ncfile=os.path.join(path,ncfile)
ncfile=Dataset(ncfile, 'r+', 'NETCDF4')
TSFC=ncfile.variables['T_SFC'][:]
fillvalue=ncfile.variables['T_SFC']._FillValue
TSFC=MA.masked_values(TSFC, fillvalue)
ncfile.close()
if not is instance(a,N.ndarray):
a=TSFC
else:
N.maximum(a, TSFC, out=a)
HTH,
Derek
> big_array=N.ma.concatenate(all_TSFC)
> Max=big_array.max(axis=0)
> print "max is", Max,"a is", a
>
_______________________________________________
NumPy-Discussion mailing list
NumPy-Discussion@scipy.org
http://mail.scipy.org/mailman/listinfo/numpy-discussion
