From f1a885770465bbfb227d0a4a20bc4cf3ed04c326 Mon Sep 17 00:00:00 2001
From: "jean-matthieu.monnet" <jean-matthieu.monnet@inrae.fr>
Date: Fri, 2 Jun 2023 08:11:29 +0200
Subject: [PATCH] Added "start" parameter in raster_metrics to align on
predefined grid
---
DESCRIPTION | 2 +-
R/raster_metrics.R | 8 ++++++--
man/raster_metrics.Rd | 5 +++++
3 files changed, 12 insertions(+), 3 deletions(-)
diff --git a/DESCRIPTION b/DESCRIPTION
index cc15060..4112828 100755
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -1,6 +1,6 @@
Package: lidaRtRee
Type: Package
-Version: 4.0.5
+Version: 4.0.6
Title: Forest Analysis with Airborne Laser Scanning (LiDAR) Data
Date: 2023-04-05
Authors@R: c(
diff --git a/R/raster_metrics.R b/R/raster_metrics.R
index 63c0be3..9ff411c 100755
--- a/R/raster_metrics.R
+++ b/R/raster_metrics.R
@@ -17,12 +17,15 @@
#' @param fun function. Function to compute metrics in each aggregated cell from
#' the values contained in the initial raster (use x$layer to access raster
#' values) / data.frame (use x$colum_name to access values)
+#' @param start vector of x and y coordinates for the reference raster. Default is (0,0) meaning that the grid aligns on (0,0).
#' @param output string. indicates the class of output object "raster" for a SpatRaster or "data.frame"
#' @return a data.frame with the XY center coordinates of the aggregated cells,
#' and the values computed with the user-specified function, or a SpatRaster object
#' @examples
#' data(chm_chablais3)
#' chm_chablais3 <- terra::rast(chm_chablais3)
+#' # replace NA with zeros
+#' chm_chablais3[is.na(chm_chablais3)] <- 0
#'
#' # raster metrics from raster
#' metrics1 <- raster_metrics(chm_chablais3, res = 10)
@@ -55,6 +58,7 @@ raster_metrics <-
fun = function(x) {
data.frame(mean = mean(x[, 3]), sd = stats::sd(x[, 3]))
},
+ start = c(0, 0),
output = "raster") {
if (inherits(r, "SpatRaster")) {
# convert to data.frame
@@ -76,8 +80,8 @@ raster_metrics <-
# return NULL if empty
if (nrow(st) == 0) return(NULL)
# compute coordinates of new cell center at metrics resolution
- dummy <- data.frame(X = round((st[, 1] - res / 2) / res) * res + res / 2,
- Y = round((st[, 2] - res / 2) / res) * res + res / 2)
+ dummy <- data.frame(X = round((st[, 1] - start[1] - res / 2) / res) * res + start[1] + res / 2,
+ Y = round((st[, 2] - start[2]- res / 2) / res) * res + start[2] + res / 2)
# compute metrics by grouping factor
dummy <- lapply(split(st, list(dummy$X, dummy$Y), sep = "_"), FUN = fun)
# convert to data.frame
diff --git a/man/raster_metrics.Rd b/man/raster_metrics.Rd
index 5d9afdd..ca87775 100755
--- a/man/raster_metrics.Rd
+++ b/man/raster_metrics.Rd
@@ -11,6 +11,7 @@ raster_metrics(
fun = function(x) {
data.frame(mean = mean(x[, 3]), sd = stats::sd(x[, 3]))
},
+ start = c(0, 0),
output = "raster"
)
}
@@ -24,6 +25,8 @@ of r resolution if a raster is provided}
the values contained in the initial raster (use x$layer to access raster
values) / data.frame (use x$colum_name to access values)}
+\item{start}{vector of x and y coordinates for the reference raster. Default is (0,0) meaning that the grid aligns on (0,0).}
+
\item{output}{string. indicates the class of output object "raster" for a SpatRaster or "data.frame"}
}
\value{
@@ -39,6 +42,8 @@ as a data.frame with the XY coordinates of the larger cells, or as SpatRaster.
\examples{
data(chm_chablais3)
chm_chablais3 <- terra::rast(chm_chablais3)
+# replace NA with zeros
+chm_chablais3[is.na(chm_chablais3)] <- 0
# raster metrics from raster
metrics1 <- raster_metrics(chm_chablais3, res = 10)
--
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