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<p>Thank you very much for your kind suggestion.</p>
<p>My bad data lie below 0 and good data is above 0 then maskout will work.</p>
<p>But what if while taking area average,</p>
<p>For example</p>
<p>set lat 0 40</p>
<p>set lon 50 110</p>
<p>maskout (var,var)</p>
<p>d ave (var,t=1,t=60)</p>
<p>Will this reject negative values (below 0) while calculating average from month 1 to 60.</p>
<p>Thanks in advance</p>
<p>Sachin</p>
<p> <font size="2">
<br />
<br />Sachin D Ghude
<br />Scientist
<br />Indian Institute of Tropical Meteorology
<br />Pashan, Pune 411008, INDIA
<br />Phone: 091-020-25883879-215 (O)
<br />FAX:091-020-25893825 (O)
<br />091-020-25899839 (R)
<br />0919371904178 (M)
<br />
<br /><b>---------- Original Message -----------</b>
<br />From: Douglas Clark <dbcl@ceh.ac.uk />
<br />To: GRADSUSR@LIST.CINECA.IT
<br />Sent: Mon, 26 Mar 2007 10:03:35 +0100
<br />Subject: Re: skipping negative values in GRADS
<br />
<br />> Sachin,
<br />>
<br />> You may be able to use the maskout function (see GrADS documentation).
<br />>
<br />> e.g. d maskout(field1,field1)
<br />> will only display values where field1>=0. Can also be used when defining a new variable.
<br />>
<br />> You can choose to include some negative values by using an offset, eg
<br />> d maskout(field1,field1+10)
<br />>
<br />> If your "bad" data lie outside the range of all "good" data, them maskout should be easy enough, otherwise you may have to do a bit more work (e.g. to maskout a range of values).
<br />>
<br />> Doug
<br />>
<br />> >>> sachinghude@TROPMET.RES.IN 26/03/2007 10:10 >>>
<br />>
<br />> some technical problem occurred while sending this mail. Therefore, i am repeating the same mail.
<br />> If you have already received this mail, excuse me for repetition.
<br />> Dear All,
<br />> I have 5-years of monthly data in nc formate. The values ranges from -999 to 500 unit. -999 is undef however, there are also some negative values in between -999 and 0. I gathered that values below 0 is because of some retrieval error. when I looked into the data I found that these negative vales dosen't appear regularly for every month/year for the same gird point. While taking (1)area average, (2)plotting time series and (3) plotting climatological mean for a particular geographical location I want to skip these negative values for all of the above calculation.
<br />> Would somebody please tell me what to do next as i do not have a much skill in grads.
<br />> Sachin D Ghude
<br />>
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<br /><b>------- End of Original Message -------</b>
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