6.1.2. Spatial Subsetting

6.1.2.1. Operation


Operation name

Spatial Subsetting

Description

This Operation provides the functionality to select data of a region of interest. All data outside will be discarded.

Utilised in

Use Case #9 Workflow


6.1.2.2. Options


name

polygon subsetting

description

spatial subsetting of data inside a polygon


name

polygon subsetting by selection from a list of main regions

description

analysis of propagation of uncertainties during geometric adjustment


name

point subsetting

description

selection of a spatial point to retrieve all temporal in formation of that point


6.1.2.3. Input data


name

longitude (lon, x)

type

floating point number

range

[-180.; +180.] respectively [0.; 360.]

dimensionality

vector

description

grid information on longitudes


name

latitude (lat, y)

type

floating point number

range

[-90.; +90.]

dimensionality

vector

description

grid information on latitudes


name

height (z)

type

floating point number

range

[-infinity; +infinity]

dimensionality

vector

description

grid information on height/depth


name

time (time, t)

type

integer or double

range

[0; +infinity]

dimensionality

vector

description

days/months since …


name

variable

type

floating point number

range

[-infinity; +infinity]

dimensionality

cube or 4D

description

values of a certain variable


6.1.2.4. Output data


name

subset of variable

type

floating point number

range

[-infinity; +infinity]

dimensionality

cube or 4D

description

values of a certain variable for the chosen area of interest


6.1.2.5. Parameters


name

lon, x (longitudinal position)

type

floating point number

valid values

[-180.; +180.] resp. [0.; 360.]

description

longitudinal coordinate of point of interest


name

lat, y (latitudinal position)

type

floating point number

valid values

[-90.; +90.]

description

latitudinal coordinate of point of interest


name

lon1, x1 (longitudinal position)

type

floating point number

valid values

[-180.; +180.] respectively [0.; 360.]

default value

minimum longitude of input data

description

longitudinal coordinate limiting rectangular area of interest


name

lon2, x2 (longitudinal position)

type

floating point number

valid values

[-180.; +180.] resp. [0.; 360.]

default value

maximum longitude of input data

description

longitudinal coordinate limiting rectangular area of interest


name

lat1, y1 (latitudinal position)

type

floating point number

valid values

[-90.; +90.]

default value

minimum latitude of input data

description

latitudinal coordinate limiting rectangular area of interest


name

lat2, y2 (latitudinal position)

type

floating point number

valid values

[-90.; +90.]

default value

maximum latitude of input data

description

latitudinal coordinate limiting rectangular area of interest


more coordinates necessary for non-rectangular areas and 3D data


6.1.2.6. Example

#     Fortran example code for spatial subsetting/sub-setting
c     Spatial Subsetting
c-----Example region: n3.4
      x1=190.
      x2=240.
      y1=-5.
      y2=5.

      data_new=0.

      do t=1,nt
        do y=1,ny
          do x=1,nx
            if(lat(y).lt.y1.or.lat(y).gt.y2)then
              continue
            elseif(lon(x).lt.x1.or.lon(x).gt.x2)then
              continue
            else
              data_new(x,y,t)=data_old(x,y,t)
            endif
          enddo !x
        enddo !y
      enddo !t
c-----------------------------------------------------------