# [ncl-talk] cnConstFEnableFill to enable fill

Rashed Mahmood rashidcomsis at gmail.com
Fri Aug 30 11:09:36 MDT 2019

```In addition, I am also not sure about the outer loop in the following, it
seems that after every iteration a and will be zero, if so, why do you need
the outer loop::

do k=0,p-1
a(k) = 0
b(k) = 0
do t=0,N-1
a(k) = a(k) +(2/N)*( in(t)*cos(2*pi*k*t/N) )
b(k) = b(k) +(2/N)*( in(t)*sin(2*pi*k*t/N) )
end do
end do

On Fri, Aug 30, 2019 at 8:37 AM Dennis Shea <shea at ucar.edu> wrote:

> function fftwavenumber (in)    ==> function fftwavenumber (in[*]:numeric)
> ====
>       return(outpuy)
> ====
>
> Ypu should test the function.
>
>
>
> On Thu, Aug 29, 2019 at 7:53 PM Md. Jalal Uddin <dmjalal90 at gmail.com>
> wrote:
>
>> Sorry, sir. It was my mistake as I am making a function in NCL for the
>> first time. The following function,  I used for rainfall analysis, produced
>> a constant 0 value.
>>
>> undef ("fftwavenumber")
>> function fftwavenumber (in)
>>
>> local in,p,a,b,c,d,f,output
>>
>> begin
>>     N=dimsizes(in)
>>
>>    if mod(N,2).eq.0 then
>>          p=N/2     ; N even
>>    else
>>          p=(N-1)/2 ; N odd
>>    end if
>>
>> pi=3.1416
>>
>> a = new((/ p /), typeof(in),getVarFillValue(in))
>> b = new((/ p /), typeof(in),getVarFillValue(in))
>>
>> do k=0,p-1
>>    a(k) = 0
>>    b(k) = 0
>>   do t=0,N-1
>>       a(k) = a(k) +(2/N)*( in(t)*cos(2*pi*k*t/N) )
>>       b(k) = b(k) +(2/N)*( in(t)*sin(2*pi*k*t/N) )
>>   end do
>> end do
>>
>> f = new((/ k,t /), typeof(in),getVarFillValue(in))
>> output = new((/ t /), typeof(in),getVarFillValue(in))
>>
>> do t=0,N-1
>>    do k=0,p-1
>>         f(k,t) = a(k)*cos(2*pi*k*t/N)+ b(k)*sin(2*pi*k*t/N)
>>    end do
>>    output(t)=(sum(f(0,t)))  ; 0 used for wave number one
>> end do
>>
>> end
>>
>> Any advice would be appreciated.
>>
>> On Thu, 29 Aug 2019 at 22:02, Dennis Shea <shea at ucar.edu> wrote:
>>
>>> Your response makes no sense to me.
>>> *ezfftf_n*
>>> <https://www.ncl.ucar.edu/Document/Functions/Built-in/ezfftf_n.shtml>
>>> *ezfftb_n*
>>> <https://www.ncl.ucar.edu/Document/Functions/Built-in/ezfftb_n.shtml>
>>>
>>> There are other FFT woutines ... look for them
>>>
>>> On Wed, Aug 28, 2019 at 9:20 PM Md. Jalal Uddin via ncl-talk <
>>> ncl-talk at ucar.edu> wrote:
>>>
>>>> Yes, sir. The variable got 0 value. Actually, it was a function in
>>>> Matlab for Fourier Decomposition (wavenumber 1). I am trying to transfer
>>>> into NCL. I would be happy to know if such function is available in NCL.
>>>>
>>>> On Wed, 28 Aug 2019 at 15:33, Rashed Mahmood <rashidcomsis at gmail.com>
>>>> wrote:
>>>>
>>>>> There is not enough information to say for sure, however, this is
>>>>> likely due to missing data values. Did you check if the variable that you
>>>>> trying to plot got missing values?
>>>>>
>>>>> Cheers,
>>>>> Rashed
>>>>>
>>>>> On Wed, Aug 28, 2019 at 6:49 AM Md. Jalal Uddin via ncl-talk <
>>>>> ncl-talk at ucar.edu> wrote:
>>>>>
>>>>>> Hi all,
>>>>>>
>>>>>> I got the following error message with a blank figure (attached).
>>>>>> *warning:ContourPlotInitialize: scalar field is constant; no contour
>>>>>> lines will appear; use cnConstFEnableFill to enable fill*
>>>>>>
>>>>>> I set a resource that did not work.
>>>>>> cnres at cnConstFEnableFill  = True
>>>>>>
>>>>>>
>>>>>> Jalal
>>>>>> --
>>>>>> *Md. Jalal Uddin*
>>>>>> MSc in Applied Meteorology
>>>>>> Nanjing University of Information, Science and Technology, China
>>>>>> B.Sc. in Disaster Management (Hons.)
>>>>>> Patuakhali Science and Technology University, Bangladesh.
>>>>>> Cell: +8613260859092, +8801792052662
>>>>>> Web: www.dmjalal90.weebly.com
>>>>>> _______________________________________________
>>>>>> ncl-talk mailing list
>>>>>> ncl-talk at ucar.edu
>>>>>> List instructions, subscriber options, unsubscribe:
>>>>>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>>>>>
>>>>>
>>>>
>>>> --
>>>> *Md. Jalal Uddin*
>>>> MSc in Applied Meteorology
>>>> Nanjing University of Information, Science and Technology, China
>>>> B.Sc. in Disaster Management (Hons.)
>>>> Patuakhali Science and Technology University, Bangladesh.
>>>> Cell: +8613260859092, +8801792052662
>>>> Web: www.dmjalal90.weebly.com
>>>> _______________________________________________
>>>> ncl-talk mailing list
>>>> ncl-talk at ucar.edu
>>>> List instructions, subscriber options, unsubscribe:
>>>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>>>
>>>
>>
>> --
>> *Md. Jalal Uddin*
>> MSc in Applied Meteorology
>> Nanjing University of Information, Science and Technology, China
>> B.Sc. in Disaster Management (Hons.)
>> Patuakhali Science and Technology University, Bangladesh.
>> Cell: +8613260859092, +8801792052662
>> Web: www.dmjalal90.weebly.com