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<div>If you have already filtered out all the reflectivities below 50
DBZ you can now use 'const' to set all nonmissing values to 1.0 and
then use 'sum' to get a count of how many occur.</div>
<div><br></div>
<div>Mike Timlin</div>
<div><br></div>
<div><br></div>
<div>Hello GrADS users,<br>
<br>
I am working on severe weather radar climatologies of parameters such
as the frequency of 50+ DBZ over an area. I have downloaded
radar data from NCDC and converted it to GrADS Binary format.
Then, I changed the descriptor file for one day and made it a
template so that it would aggregate all radar files for one day.
For each day, I can filter out any values less than 50 dBZ and define
it as its own variable. <br>
<br>
I want to take all of these filtered out images and sum them up for
the day, and for each year between the months of May and August
for all days in which severe weather was reported. In this
way, the frequency of 50+ DBZ over a certain area over the course of a
summer season or a series of summer seasons can be calculated.
Is there a way to loop through .ctl aggregate files for each day in
order to accomplish this or can a loop be created in which each
data file is opened, then the filter is applied, and then the file is
closed? The only problem is that the time intervals between
successive radar images are not evenly spaced apart; sometimes there
would be 4 minutes in between and sometimes there would be 10
minutes. I have tried to apply the filtering over one day to an
aggregate file and an error comes up regarding the inability to
allocate enough memory to complete the operation.<br>
<br>
<br>
John M<br>
</div>
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