6.1.3. Spatial Subsetting
6.1.3.1. 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
6.1.3.2. 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
6.1.3.3. 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
6.1.3.4. Output data
- name
subset of variable
- type
floating point number
- range
[-infinity; +infinity]
- dimensionality
vector or cube or 4D
- description
values of a certain variable for the chosen area of interest
6.1.3.5. 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
6.1.3.6. 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-----------------------------------------------------------