From: Dennis Shea <shea_at_nyahnyahspammersnyahnyah>

Date: Tue Feb 08 2011 - 10:37:47 MST

Date: Tue Feb 08 2011 - 10:37:47 MST

Please read the documentation associated with

http://www.ncl.ucar.edu/Document/Functions/Contributed/obj_anal_ic_deprecated.shtml

If this does not work, you will have to write your own

interpolation function.

Good luck

On 2/8/11 9:46 AM, Debasish wrote:

*>
*

*> Dear Dennis
*

*>
*

*> Thanks for your response.
*

*>
*

*>> I am not clear what you mean by
*

*>> "interpolate 2d randomly-spaced data to
*

*>> another 2d randomly-spaced data or 2d randomly
*

*>> spaced data to directly RCMs grid"
*

*>>
*

*> My primary aim is to interpolate 2d random spaced data to RCM grid
*

*>
*

*> For example, I have 2d random spaced data x(npts) with lat(npts) and
*

*> lon(npts). I would like to interpolate the data to RCM grid i.e.
*

*> lat2d(m,n) and lon2d(m,n) and interpolated output should be xint(m,n)
*

*>
*

*> I believe there is two ways to solve this
*

*>
*

*> [1]
*

*> direct interpolation of 2d random spaced data on to RCM grid
*

*>
*

*> [2]
*

*> First interpolate 2d random spaced data to another 2d random spaced data
*

*> and then convert new random space data to RCM grid
*

*>
*

*> Assume, function points2points(X[*],Y[*],z[*].X1[*],Y1[*],opts:logical)
*

*>
*

*> step1: lat1d = ndtooned(lat2d)
*

*> lon1d = ndtooned(lon2d)
*

*>
*

*> step2: xint1d = points2points(lon(npts),lat(npts),x(npts),lon1d(m x n),
*

*> lat1d(m x n), opts)
*

*>
*

*> step3: xint = onedtond(xint1d, (/yc,x/))
*

*>
*

*>> ---
*

*>>
*

*>> There is a function in NCL' contributed.ncl that may work.
*

*>> Like "natgrid" this can be slow!!!!
*

*>>
*

*>> function obj_anal_ic_deprecated(X[*],Y[*],Z[*],lon:numeric,lat:numeric \
*

*>> ,dcrit[*]:numeric, opt:logical)
*

*>>
*

*>> ===
*

*>> opt = 0
*

*>> zrcm = obj_anal_ic_deprecated(loni,lati,zi, dcrit, lon2d,lat2d, opt)
*

*>>
*

*>> input: loni[*], lati[*], zi[*]
*

*>>
*

*>> output: lon2d[*][*], lat2d[*][*]
*

*>>
*

*>> ; dcrit - 1D array containing successive radii of influence.
*

*>> ; Must be expressed in degrees latitude and should be
*

*>> ; monotonically de. eg: dcrit = (/5, 3/)
*

*>>
*

*> I believe that function "obj_anal_ic_deprecated" will works for me
*

*> however I have few questions regarding the function.
*

*>
*

*> [1]
*

*> Do you know which version the function is created? because when I try to
*

*> use it according to the webpage example
*

*> (http://www.ncl.ucar.edu/Document/Functions/Contributed/obj_anal_ic_deprecated.shtml)
*

*> it does not recognized the function:
*

*> fatal:Undefined identifier: (obj_anal_ic_deprecated) is undefined, can't
*

*> continue
*

*> I already load the
*

*> "$NCARG_ROOT/lib/ncarg/nclscripts/csm/contributed.ncl" and I am using
*

*> NCL version 5.1.1
*

*>
*

*> [2]
*

*> I would like to clarify that in webpage of the function output lat, lon
*

*> is 1dimensional so I need to follow the method [2] (mentioned above) or
*

*> can I use 2dimension lat (lat2d) and lon(lon2d) too (method[1]). If like
*

*> to use lat2d(m,n) and lon2d(m,n) and corresponding output(m,n), what are
*

*> the modifications?
*

*>
*

*> [3]
*

*> rscan (in webpage) or dcrit (in your script) can be one dimensional
*

*> array of any length or is there any particular reason to choose length 2
*

*> or length 3 with respect to the accuracy
*

*>
*

*> Thank again for your help
*

*>
*

*> Debasish
*

*>
*

*> On 2/7/11 9:59 AM, Debasish wrote:
*

*>>> Hello,
*

*>>>
*

*>>> Thanks Dennis for your suggestion. However I believe the function
*

*>>> "triple2grid2d" places randomly-spaced data onto the nearest
*

*>>> locations of a grid instead of interpolation while I need to do a
*

*>>> interpolation. I also checked
*

*>>> http://www.ncl.ucar.edu/Document/Functions/regrid.shtml but did not
*

*>>> find any function that can interpolate randomly-spaced data to
*

*>>> another randomly-spaced data or RCMs grid.
*

*>>>
*

*>>> Therefore, I would like to know is there any function or any way in
*

*>>> NCL to interpolate 2d randomly-spaced data to another 2d
*

*>>> randomly-spaced data or 2d randomly spaced data to directly RCMs grid.
*

*>>>
*

*>>> Any help in this regard will be appreciated and sorry for any
*

*>>> inconvenience
*

*>>>
*

*>>> Thanks
*

*>>>
*

*>>> Debasish
*

*>>>
*

*>>>
*

*>>>
*

*>>>
*

*>>> On 2011-02-03, at 14:36, Dennis Shea wrote:
*

*>>>
*

*>>>> NCL does not read Excel spradsheeys.
*

*>>>> You would have to convert to ascii, the use asciiread.
*

*>>>>
*

*>>>> "natvar" is high quality but is known to be slow.
*

*>>>>
*

*>>>> Really, if you have a large number of high res\
*

*>>>> grids you need interpolated to an RCM grid,
*

*>>>> there is not magic bullet. it will take time.
*

*>>>>
*

*>>>> The following *may* be useful.
*

*>>>>
*

*>>>>
*

*>>>> http://www.ncl.ucar.edu/Document/Functions/Built-in/triple2grid2d.shtml
*

*>>>>
*

*>>>> Good luck
*

*>>>>
*

*>>>> On 2/3/11 12:02 PM, Debasish wrote:
*

*>>>>> Dear NCL Users
*

*>>>>>
*

*>>>>> I guess I am getting missing outputs because of the assumption that xin
*

*>>>>> is gridded RCM data because neither lon proceeds left to right nor lat
*

*>>>>> proceeds from south-to-north.
*

*>>>>>
*

*>>>>> I have tried to use "natgrid" assuming xi (mxn) with lat(mxn) and
*

*>>>>> lon(mxn) but the program is hang. I guess it does not work too.
*

*>>>>>
*

*>>>>> Therefore, I would like to know how do I interpolate this data (high
*

*>>>>> resolution data) to RCM grid with lat2d(172,180), lon2d(172,180).
*

*>>>>> Meanwhile I counted that there are nearly 450 RCM grid over the input
*

*>>>>> domain; so I would like to interpolate the input data to this 450 CRCM
*

*>>>>> grid.
*

*>>>>> I am sending the part (total file has 17536 lat, lon and xin) of
*

*>>>>> lat and
*

*>>>>> lon of the input data for your convenience .
*

*>>>>>
*

*>>>>> Any help in this regard will be appreciated
*

*>>>>>
*

*>>>>> Thanks
*

*>>>>>
*

*>>>>> Debasish
*

*>>>>>
*

*>>>>> =
*

*>>>>>
*

*>>>>>
*

*>>>>>
*

*>>>>> Begin forwarded message:
*

*>>>>>
*

*>>>>>> *From: *Debasish<debasish@sca.uqam.ca<mailto:debasish@sca.uqam.ca>>
*

*>>>>>> *Date: *1 février 2011 16:42:48 HNE
*

*>>>>>> *To: *Ncl Talk<ncl-talk@ucar.edu<mailto:ncl-talk@ucar.edu>>
*

*>>>>>> *Subject: **[ncl-talk] interpolation gridded data to rcm*
*

*>>>>>>
*

*>>>>>> Dear NCL users,
*

*>>>>>>
*

*>>>>>> I have gridded data xin (m,n) with lat(m,n) and lon(m,n) for smaller
*

*>>>>>> domain. I would like to interpolate the data to RCM grid lat2d(a,b)
*

*>>>>>> and lon2d(a,b) for bigger domian.
*

*>>>>>> I follow the followings steps:
*

*>>>>>>
*

*>>>>>> 1. I assume "xin" as RCM gridded data
*

*>>>>>> 2. convert lat2d and lon2d to 1d array lat1d and lon1d
*

*>>>>>> 3. Use "rcm2points" function
*

*>>>>>> xout1d = rcm2points(lat,lon,xin,lat1d,lon1d,0)
*

*>>>>>> 4. then convert xout1d to 2d
*

*>>>>>> but all the values of xout1d are missing
*

*>>>>>>
*

*>>>>>> Any suggestion to fix these problem will be appreciated
*

*>>>>>>
*

*>>>>>> Thanks
*

*>>>>>>
*

*>>>>>> Debasish
*

*>>>>>> _______________________________________________
*

*>>>>>> ncl-talk mailing list
*

*>>>>>> List instructions, subscriber options, unsubscribe:
*

*>>>>>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
*

*>>>>>
*

*>>>>> =
*

*>>>>>
*

*>>>>>
*

*>>>>>
*

*>>>>> _______________________________________________
*

*>>>>> ncl-talk mailing list
*

*>>>>> List instructions, subscriber options, unsubscribe:
*

*>>>>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
*

*>>>
*

*>>> _______________________________________________
*

*>>> ncl-talk mailing list
*

*>>> List instructions, subscriber options, unsubscribe:
*

*>>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
*

*>
*

_______________________________________________

ncl-talk mailing list

List instructions, subscriber options, unsubscribe:

http://mailman.ucar.edu/mailman/listinfo/ncl-talk

Received on Tue Feb 8 10:37:53 2011

*
This archive was generated by hypermail 2.1.8
: Fri Feb 11 2011 - 16:11:42 MST
*