use regexp to find specific names.

Hi

I've been trying to download some specific files from the web with name

'DPR-NS-12755-V04A.MRMS-XXXXXXXX.114200.matched-130W_55W_20N_55N.extract.dat'

The XXXXXXXX is the yyyymmdd that changes with the loop. I used regexp. But it returns just XXXXXXXX and not the entire name. I used something ugly (which worked finally) to download my file as:

expr = [sprintf('%02.0f', y), sprintf('%02.0f', m),  sprintf('%02.0f', d)]; 
% y = year, m = month, d is day
a  = regexp(str,expr);
filename=str(a-22:a+51);

I know it is very armature to use something like this!. Can you help me to parcel the name of these files in a more professional way? I read the regexp doc in Matlab but it is a little confusing for me.

Thanks,

Zeinab

Answer 1

[mizuki]

Use datetime instead of regular expressions:

% from 2016/12/01 to 2016/12/10 with every other day
datevec = datetime(2016,12,01):day(2):datetime(2016,12,10);
t = datestr(datevec, 'yyyymmdd');
for i = 1:size(t,1)
    filename = ['DPR-NS-12755-V04A.MRMS-', t(i,:), '114200.matched-130W_55W_20N_55N.extract.dat'];
    % webread(filename)
end

[FaryTak]

Thanks. The problem is DPR-NS-12755-V04A.MRMS is also changing from day to day, so it is not a fixed name.

[per isakson]

How do you know the name of the day?

[FaryTak]

I know there is one file for each day. I can find them by YYYYMMDD going through each day of a year. But the rest of the name starts with "DPR" and ends with ".dat". the other parts of the file's names are unknown.