vm_c_frac_mn.Rd
This function allows you to calculate the mean value of fractal dimension index of all patches belonging to class i in a categorical landscape in vector data format The index is based on the patch perimeter and the patch area and describes the patch complexity
vm_c_frac_mn(landscape, class_col)
the input landscape image,
the name of the class column of the input landscape
the returned calculated mean value of each class is in column "value", and this function returns also some important information such as level, class number and metric name. Moreover, the "id" column, although it is just NA here at class level. we need it because the output struture of metrics at class level should correspond to patch level one by one, and then it is more convinient to combine metric values at different levels and compare them.
vm_c_frac_mn(vector_landscape, "class")
#> # A tibble: 3 × 5
#> level class id metric value
#> <chr> <chr> <chr> <chr> <dbl>
#> 1 class 1 NA frac_mn 2.15
#> 2 class 2 NA frac_mn 1.99
#> 3 class 3 NA frac_mn 1.93