Subset a plan position indicator (ppi)

Source: R/ppi.R

Select parameters (param) or derived quantities by index from a plan position indicator (ppi).

# S3 method for ppi
[(x, i)

Arguments

x

A ppi object.

i

Integer. Index/indices specifying which parameters (param) or derived quantities to extract.

Value

A ppi object containing a subset of parameters (param).

Examples

# Project a scan as a ppi
ppi <- project_as_ppi(example_scan)
#> Warning: CRS object has comment, which is lost in output; in tests, see
#> https://cran.r-project.org/web/packages/sp/vignettes/CRS_warnings.html

# This ppi contains 5 parameters (DBZH VRADH ZDR RHOHV PHIDP)
ppi
#>                Plan position indicator (class ppi)
#> 
#>   parameters:  DBZH VRADH RHOHV ZDR PHIDP 
#>         dims:  201 x 200 pixels
#> 

# Subset ppi to one containing only the first parameter (DBZH)
ppi[1]
#>                Plan position indicator (class ppi)
#> 
#>   parameters:  DBZH 
#>         dims:  201 x 200 pixels
#> 

# Subset ppi to one containing the first three parameters (DBZH, VRADH, ZDR)
ppi[1:3]
#>                Plan position indicator (class ppi)
#> 
#>   parameters:  DBZH VRADH RHOHV 
#>         dims:  201 x 200 pixels
#> 

# Subset ppi to one without the first 2 parameters (ZDR RHOHV PHIDP)
ppi[-1:-2]
#>                Plan position indicator (class ppi)
#> 
#>   parameters:  RHOHV ZDR PHIDP 
#>         dims:  201 x 200 pixels
#>