在R中,我使用焦点函数来模糊一些光栅。到目前为止,我正在单独阅读每个光栅,应用焦点(请参见下面的代码),然后移动到下一个光栅等。单独读取和应用函数到每个光栅的过程非常耗时,因为我有许多研究地点的多个光栅。
我想做的是读取位于文件夹中的光栅,并以自动化的方式应用焦点函数。也就是说,该函数应该读取文件夹中的每个光栅,然后将准确地应用我对每个光栅使用的代码。这样,我唯一需要设置的参数将是工作目录。
这就是我目前所做的:
library(terra)
wd = "C:/Users/nikos/OneDrive/Desktop/psf_paris2/"
# read the rasters
pop = rast(paste0(wd, "pop.tif"))
# focal for every raster
# raster named pop
for (i in seq(from = 0.2, to = 0.8, by = 0.2)) {
print(i)
gf <- focalMat(pop, i * 400, "Gauss")
r_gf <- focal(pop, w = gf, na.rm = TRUE)
r_gf = aggregate(r_gf, fact = 4, fun = "mean", cores = 8)
stringedi = gsub("\\.", "", toString(format(i, nsmall = 2)))
writeRaster(r_gf,
paste0("C:/Users/nikos/OneDrive/Desktop/psf_paris2/pop",
stringedi, ".tif"),
overwrite=TRUE)
}
下面是一个光栅:
pop = raster(new("RasterLayer", file = new(".RasterFile", name = "C:\\Users\\Geography\\Desktop\\focal\\pop.tif",
datanotation = "FLT4S", byteorder = "little", nodatavalue = -Inf,
NAchanged = FALSE, nbands = 1L, bandorder = "BIL", offset = 0L,
toptobottom = TRUE, blockrows = c(rows = 5L), blockcols = c(cols = 358L),
driver = "gdal", open = FALSE), data = new(".SingleLayerData",
values = logical(0), offset = 0, gain = 1, inmemory = FALSE,
fromdisk = TRUE, isfactor = FALSE, attributes = list(), haveminmax = TRUE,
min = 0.43411433696747, max = 355.74725341797, band = 1L,
unit = "", names = "pop"), legend = new(".RasterLegend",
type = character(0), values = logical(0), color = logical(0),
names = logical(0), colortable = logical(0)), title = character(0),
extent = new("Extent", xmin = 165700, xmax = 201500, ymin = 5735500,
ymax = 5769600), rotated = FALSE, rotation = new(".Rotation",
geotrans = numeric(0), transfun = function ()
NULL), ncols = 358L, nrows = 341L, crs = new("CRS", projargs = "+proj=moll +lon_0=0 +x_0=0 +y_0=0 +datum=WGS84 +units=m +no_defs"),
srs = "+proj=moll +lon_0=0 +x_0=0 +y_0=0 +datum=WGS84 +units=m +no_defs",
history = list(), z = list()))
2条答案
按热度按时间ivqmmu1c1#
文件名问题的解决方案:
j5fpnvbx2#
创建一个函数,你想做的每一个图片,然后只是循环通过所有的文件