lakemorpho (version 1.0.2)

lakeMaxLength: Caluclate maximum lake length

Description

Maximum lake length is defined as the longest open water distance of a lake. This function determines the maximum lake length of lake by comparing the lenghts of a user defined number of lines. The user specifies a number of points to distribute along the lake shoreline and the point to point line lengths are checked for multiple intersections (i.e. line not just open water),starting with the longest line first. Function is currently very sensitive to pointDens and slows down considerably for larger values. Small values of point dens are acceptable for lakes withtout complex shorelines. Care needs to be taken in selecting an approriate pointDens and multiple values should be checked to ensure stability in the estimates.

Usage

lakeMaxLength(inLakeMorpho, pointDens, addLine = T)

Arguments

inLakeMorpho

An object of lakeMorphoClass. Output of the lakeSurroundTopo function would be appropriate as input

pointDens

Number of points to place equidistant along shoreline. The maximum point to point distance that does not also intersect the shoreline is used. To total of n*(n-1)/2 comparisons is possible, but in practice is usually significant less.

addLine

Boolean to determine if the selected max length line should be added to the inLakeMorpho object. Defaults to True

Value

This returns a numeric value indicating the length of the longest line possible in the lake. Units are the same as the input data.

References

Florida LAKEWATCH (2001). A Beginner's guide to water management - Lake Morphometry (2nd ed.). Gainesville: Florida LAKEWATCH, Department of Fisheries and Aquatic Sciences. Link

Examples

data(lakes)
lakeMaxLength(inputLM,50)