Related Circumscribing Circle (Shape metric)
lsm_p_circle(landscape, directions = 8)tibble
Raster* Layer, Stack, Brick, SpatRaster (terra), stars, or a list of rasterLayers.
The number of directions in which patches should be connected: 4 (rook's case) or 8 (queen's case).
$$CIRCLE = 1 - (\frac{a_{ij}} {a_{ij}^{circle}})$$ where \(a_{ij}\) is the area in square meters and \(a_{ij}^{circle}\) the area of the smallest circumscribing circle.
CIRCLE is a 'Shape metric'. The metric is the ratio between the patch area and the smallest circumscribing circle of the patch. The diameter of the smallest circumscribing circle is the 'diameter' of the patch connecting the opposing corner points of the two cells that are the furthest away from each other. The metric characterises the compactness of the patch and is comparable among patches with different area.
None
0 <= CIRCLE < 1
CIRCLE = 0 for a circular patch and approaches CIRCLE = 1 for a linear patch.
McGarigal, K., SA Cushman, and E Ene. 2012. FRAGSTATS v4: Spatial Pattern Analysis Program for Categorical and Continuous Maps. Computer software program produced by the authors at the University of Massachusetts, Amherst. Available at the following web site: https://www.umass.edu/landeco/
Baker, W. L., and Y. Cai. 1992. The r.le programs for multiscale analysis of landscape structure using the GRASS geographical information system. Landscape Ecology 7: 291-302.
Based on C++ code from Project Nayuki (https://www.nayuki.io/page/smallest-enclosing-circle).
lsm_p_area,
lsm_c_circle_mn,
lsm_c_circle_sd,
lsm_c_circle_cv,
lsm_l_circle_mn,
lsm_l_circle_sd,
lsm_l_circle_cv