header_add_extrabytes: Variable length records tools

Description Usage Arguments Examples

View source: R/header_tools.r

Description

Functions that update a header to describe variable length records according to the LAS specifications

Usage

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header_add_extrabytes(header, data, name, desc)

header_add_extrabytes_manual(header, name, desc, type, offset = NULL,
  scale = NULL, max = NULL, min = NULL, NA_value = NULL)

Arguments

header

list

data

vector. Data that must be added in the extrabytes attributes.

name

character. The name of the extrabytes attributes to add in the file.

desc

character. The description of the extrabytes attributes to add in the file.

type

integer. The data type of the extrabytes attributes (page 25 of the spec).

scale, offset

numeric. The scale and offset of the data. NULL if not relevant.

min, max

numeric or integer. The minimum and maximum value of the data. NULL if not relevant.

NA_value

numeric or integer. NA is not a valid value. At writing time it will be replaced by this value that will be considered as NA. NULL if not relevant.

Examples

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data = data.frame(X = c(339002.889, 339002.983, 339002.918),
                  Y = c(5248000.515, 5248000.478, 5248000.318),
                  Z = c(975.589, 974.778, 974.471),
                  gpstime = c(269347.281418006, 269347.281428006, 269347.281438006),
                  Intensity = c(82L, 54L, 27L),
                  ReturnNumber = c(1L, 1L, 2L),
                  NumberOfReturns = c(1L, 1L, 2L),
                  ScanDirectionFlag = c(1L, 1L, 1L),
                  EdgeOfFlightline = c(1L, 0L, 0L),
                  Classification = c(1L, 1L, 1L),
                  ScanAngle = c(-21L, -21L, -21L),
                  UserData = c(32L, 32L, 32L),
                  PointSourceID = c(17L, 17L, 17L),
                  treeID = c(1L, 1L, 1L))

lasheader = header_create(data)
lasheader[["Variable Length Records"]]

lasheader = header_add_extrabytes(lasheader, data$treeID, "treeID", "An id for each tree")
lasheader[["Variable Length Records"]]

Jean-Romain/rlas documentation built on Aug. 22, 2018, 4:31 a.m.