stdmetrics - r-lidar/lidR GitHub Wiki

stdmetrics and associated functions provide an easy way to compute several common metrics. This page provide a quick description of each predefined metric because their names associated with the documentation can be not enough explicit.

• n: number of points
• area: approximative actual area of a raster (should be close to the square of the resolution but not on the edge)

• angle: average absolute scan angle
• zmax: maximum height
• zmean: mean height
• zsd: standard deviation of height distribution
• zskew: skewness of height distribution
• zkurt: kurtosis of height distribution
• zentropy: entropy of height distribution (see function entropy)
• pzabovezmean: percentage of returns above zmean
• pzabovex: percentage of returns above x.
• zqx: x^th percentile (quantile) of height distribution
• zpcumx: cumulative percentage of return in the i^th layer according to Wood et al. 2008 (see metrics named d₁, d₂, ...)

with the probability distribution of elevations. is the lower bound and was hard coded to 0 in lidR < 3.1.3 and is now a parameter in from 3.1.3. is the elevation of the highest point

• itot: sum of intensities for each return
• imax: maximum intensity
• imean: mean intensity
• isd: standard deviation of intensity
• iskew: skewness of intensity distribution
• ikurt: kurtosis of intensity distribution
• ipground: percentage of intensity returned by points classified as "ground"
• ipcumzqx: percentage of intensity returned below the k^th percentile of height
• ip1st: percentage of intensity returned by 1^st returns
• ip2nd: percentage of intensity returned by 2^nd returns
• ip3rd: percentage of intensity returned by 3^rd returns
• ipxth: percentage of intensity returned by x^th returns
• pxth: percentage x^th returns
• pground: percentage of returns classified as "ground"