Form factor/Compactness(vector data)

Calculate form factor or compactness

Usage

vm_p_comp(landscape, class_col = NULL, patch_col = NULL)

Arguments

landscape

the input landscape image,

class_col

the name of the class column of the input landscape

patch_col

the name of the id column of the input landscape

Value

the function returns tibble with the calculated values in column "value", this function returns also some important information such as level, class, patch id and metric name.

Details

Form factor (compactness) is calculated as: $$COMPACT = \frac{4\pi A}{P^2}$$ where \(A\) is the patch area (m²) and \(P\) is the perimeter (m). This is the isoperimetric quotient, ranging from 0 (linear) to 1 (circular). Higher values indicate more compact, circle-like shapes.

References

Jiao, L., Liu, Y., & Li, H. (2012). Characterizing land-use classes in remote sensing imagery by shape metrics. ISPRS Journal of Photogrammetry and Remote Sensing, 72, 46–55. https://doi.org/10.1016/j.isprsjprs.2012.05.012

Examples

vm_p_comp(vector_patches, "class", "patch")
#> # A tibble: 40 × 5
#>    level class id    metric  value
#>    <chr> <chr> <chr> <chr>   <dbl>
#>  1 patch 1     11    compact 0.363
#>  2 patch 1     12    compact 0.531
#>  3 patch 1     13    compact 0.436
#>  4 patch 1     14    compact 0.503
#>  5 patch 1     15    compact 0.785
#>  6 patch 1     16    compact 0.785
#>  7 patch 1     17    compact 0.785
#>  8 patch 1     18    compact 0.754
#>  9 patch 1     19    compact 0.785
#> 10 patch 1     20    compact 0.785
#> # ℹ 30 more rows