# Re: Where oh where

From: James Correia, Jr <jimmyc42_at_nyahnyahspammersnyahnyah>
Date: Fri Oct 28 2011 - 19:39:22 MDT

I suppose you can string a few where's together until you have the

var = where(t_ref2m .lt. condition1 .or. t_ref2m .gt. condition2, missing,
t_ref2m)

Then do another variation using rh:
var1 = where(rh .gt. rhcondition1 .or. rh .lt. condition2, missing, rh)

temp = ind(where(.not.ismissing(var) .and. .not.ismissing(var1), 1, 0))

do polynomial computation using the arrays rh(temp) and t_ref2m(temp) where
temp represents only the eements of the array that satisfy your conditions
you defined in var and var1.

Does that make sense?
jimmyc

On Fri, Oct 28, 2011 at 8:13 PM, jrbuzan <jbuzan@purdue.edu> wrote:

> Hmmm.
> I guess I left a piece of information out.
> The function is calculating a third array: hi (a polynomial that uses Temp
> and RH as inputs)
> The function (hi) only works over very specific combinations of t and rh.
>
> I could bound the Temperature range, as in your statement, however the
> relative humidity range varies as temperature varies. I am not sure how to
> continue the statement from that point.
>
> -Jonathan
>
>
> On Oct 28, 2011, at 8:58 PM, James Correia, Jr wrote:
>
> It might be complicated in fortran but I dont see how that effects the
> where in NCL.
>
> You can still write:
> var = where((t_ref2m .gt. 324.15) .or. (t_refm .lt. 293.15), Missing_value,
> t_ref2m) ; .and. would fail since 1 grid point can not have two values
>
> You can keep making changes to the array "var".
> ;code is untested
> jimmyc
>
> On Fri, Oct 28, 2011 at 7:43 PM, jrbuzan <jbuzan@purdue.edu> wrote:
>
>> Hello,
>>
>> I have complicated where statement.
>> I am not sure how to approach this in NCL. The examples do not seem
>> to show how to bound a region with 2 arrays where there is a specific
>> range that the function may be calculated.
>>
>> Is there a way to write multiple where statements within one where
>> statement?
>>
>> Thanks,
>>
>> -Jonathan
>>
>> Example code.
>> In fortran:
>>
>> WHERE ((t_ref2m.gt.324.15) .and. (t_ref2m.lt.293.15))
>> Missing value
>> ELSEWHERE
>> WHERE ((rh_ref2m.lt.10.) .and. (t_ref2m.gt.322.15))
>> Function
>> END WHERE
>> WHERE ((rh_ref2m.lt.20.) .and. (t_ref2m.gt.318.15) .and.
>> (t_ref2m.lt.322.15))
>> Function
>> END WHERE
>> WHERE ((rh_ref2m.lt.30.) .and. (t_ref2m.gt.314.15) .and.
>> (t_ref2m.lt.318.15))
>> Function
>> END WHERE
>> WHERE ((rh_ref2m.lt.40.) .and. (t_ref2m.gt.311.15) .and.
>> (t_ref2m.lt.314.15))
>> Function
>> END WHERE
>> WHERE ((rh_ref2m.lt.50.) .and. (t_ref2m.gt.308.15) .and.
>> (t_ref2m.lt.311.15))
>> Function
>> END WHERE
>> WHERE ((rh_ref2m.lt.60.) .and. (t_ref2m.gt.307.15) .and.
>> (t_ref2m.lt.308.15))
>> Function
>> END WHERE
>> WHERE ((rh_ref2m.lt.70.) .and. (t_ref2m.gt.306.15) .and.
>> (t_ref2m.lt.307.15))
>> Function
>> END WHERE
>> WHERE ((rh_ref2m.lt.80.) .and. (t_ref2m.gt.303.15) .and.
>> (t_ref2m.lt.306.15))
>> Function
>> END WHERE
>> WHERE ((rh_ref2m.lt.90.) .and. (t_ref2m.gt.301.15) .and.
>> (t_ref2m.lt.303.15))
>> Function
>> END WHERE
>> WHERE ((rh_ref2m.lt.100.) .and. (t_ref2m.gt.293.15) .and.
>> (t_ref2m.lt.301.15))
>> Function
>> END WHERE
>> END WHERE
>>
>>
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>
>
>
> --
>
> James Correia Jr.
> OU CIMMS Research Associate
> SPC HWT Liaison
>
> "The highest function of the teacher consists not so much in imparting
> knowledge as in stimulating the pupil in its love and pursuit. To know how
> to suggest is the art of teaching."
>
>
> ------------------------------------------------------------------------------------------
> The views expressed in this email do not necessarily reflect those of NOAA,
> the National Weather Service, or the University of Oklahoma.
>
> ------------------------------------------------------------------------------------------
>
>
>

```--
James Correia Jr.
OU CIMMS Research Associate
SPC HWT Liaison
"The highest function of the teacher consists not so much in imparting
knowledge as in stimulating the pupil in its love and pursuit. To know how
to suggest is the art of teaching."
------------------------------------------------------------------------------------------
The views expressed in this email do not necessarily reflect those of NOAA,
the National Weather Service, or the University of Oklahoma.
------------------------------------------------------------------------------------------

```

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Received on Fri Oct 28 19:39:31 2011

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