Drop unnecesary 'iters'

Objects of FLR classes can vary in the length along the sixth dimension in any slot of class FLQuant. This reduces object size and memory usage. If an object has been extended fully, for example by using propagate, we can slim down the object by reducing any slot where all iters are identical and keeping only yhe first iter.

Usage

slim(object, ...)

# S4 method for FLComp
slim(object, ...)

Arguments

object: A complex FLR object to slim down.

Value

An object of the same class as the input.

Details

The test for whether an slot can be slimmed is based on checking if the sum of the variance along the 6th dimensions is equal to zero.

Author

The FLR Team

Examples

data(ple4)
# Extend all of ple4 to 50 iters
ple4 <- propagate(ple4, 50)
# Add variability in catch.n
catch.n(ple4) <- rlnoise(50, log(catch.n(ple4)), log(catch.n(ple4))/10)
summary(ple4)
#> An object of class "FLStock"
#> 
#> Name: PLE 
#> Description: Plaice in IV. ICES WGNSSK 2018. FLAAP 
#> Quant: age 
#> Dims:  age 	year	unit	season	area	iter
#> 	10	61	1	1	1	50	
#> 
#> Range:  min	max	pgroup	minyear	maxyear	minfbar	maxfbar 
#> 	1	10	10	1957	2017	2	6	
#> 
#> Metrics: 
#>   rec: 367450 - 4303680  (1000) 
#>   ssb: 203391 - 913290  (t) 
#>   catch: 78360 - 315245  (t) 
#>   fbar: 0.20 - 0.72  (f) 
# slim object by dropping identical iters
sple4 <- slim(ple4)
summary(sple4)
#> An object of class "FLStock"
#> 
#> Name: PLE 
#> Description: Plaice in IV. ICES WGNSSK 2018. FLAAP 
#> Quant: age 
#> Dims:  age 	year	unit	season	area	iter
#> 	10	61	1	1	1	50	
#> 
#> Range:  min	max	pgroup	minyear	maxyear	minfbar	maxfbar 
#> 	1	10	10	1957	2017	2	6	
#> 
#> Metrics: 
#>   rec: 367450 - 4303680  (1000) 
#>   ssb: 203391 - 913290  (t) 
#>   catch: 78360 - 315245  (t) 
#>   fbar: 0.20 - 0.72  (f)