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I am trying to prepare the environmental layers (constrained in specific Asia area) for use in Maxent model. However, I ran into some error messages in the last line:

library(sp)
library(maptools)
library(rworldmap)
library(dismo)
# A specified range of Asia area that suitable for special species
tsta <- read.csv('CM10_Kop_Shp_V1.2/Asiaclip/Asiaclipt.csv',as.is=TRUE)[https://drive.google.com/file/d/0B4vIx9MCfJgfbHpINTlyUGZVbXc/view?usp=sharing][1]
tsta <- tsta[,seq(1,4)]
coordinates(tsta) = c("Lon", "Lat")
gridded(tsta) <- TRUE
ra <- raster(tsta)

# a Rasterstack contains global range of 40 bioclim variables
files3 <- list.files(path=paste
                     ("CM10_1975H_Bio_ASCII_V1.2/CM10_1975H_Bio_V1.2"),
                     , pattern='txt',full.names=TRUE )[https://www.climond.org/Core/Authenticated/Data/CM10_V1.2/CM10_Bio_V1.2/CM10_Bio_ASCII_V1.2/CM10_1975H_Bio_ASCII_V1.2.zip][1]

predictors3 <- stack(files3)
asia.predictors3 <- mask(predictors3,ra)

Error in compareRaster(x, mask) : different extent

The details for predictors3 were 

predictors3
class       : RasterStack 
dimensions  : 857, 2160, 1851120, 40  (nrow, ncol, ncell, nlayers)
resolution  : 0.1666667, 0.1666667  (x, y)
extent      : -180, 180, -59.16667, 83.66667  (xmin, xmax, ymin, ymax)
coord. ref. : NA 
names       : CM10_1975H_Bio01_V1.2, CM10_1975H_Bio02_V1.2, CM10_1975H_Bio03_V1.2, CM10_1975H_Bio04_V1.2, CM10_1975H_Bio05_V1.2, CM10_1975H_Bio06_V1.2, CM10_1975H_Bio07_V1.2, CM10_1975H_Bio08_V1.2, CM10_1975H_Bio09_V1.2, CM10_1975H_Bio10_V1.2, CM10_1975H_Bio11_V1.2, CM10_1975H_Bio12_V1.2, CM10_1975H_Bio13_V1.2, CM10_1975H_Bio14_V1.2, CM10_1975H_Bio15_V1.2, ...

The details for ra were:

ra
class       : RasterLayer 
dimensions  : 213, 290, 61770  (nrow, ncol, ncell)
resolution  : 0.1666667, 0.1666667  (x, y)
extent      : 97.5, 145.8333, 18.16667, 53.66667  (xmin, xmax, ymin, ymax)
coord. ref. : NA 
data source : in memory
names       : Location 
values      : 168505, 377653  (min, max)

My goal is to prepare a RasterLayer or Rasterstack contains all variables of "predictors3" but limited in the range of "ra". As you can see the extent of ra was included in the extent of predictors3 and their resolutions were identical. How should I fix the error?

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2 回答 2

1

ra在这种情况下，由于和的原点和分辨率predictors3相同，您可以使用crop

predictors3 <- raster(xmn=-180, xmx=180, ymn=-59.16667, ymx=83.66667, res=1/6)
ra <- raster(xmn=97.5, xmx=145.8333, ymn=18.16667, ymx=53.66667, res=1/6)

x <- crop(predictors3, ra)

在其他情况下，您可能需要使用 ( dis)aggregate或resample

于 2015-12-25T05:58:04.320 回答
0

根据上述建议，我裁剪了全球气候层“predictors3”来识别两个栅格的范围。然后，对最新的栅格进行掩码以获取特定区域内的目标变量。

asia.predictors <- crop(predictors3,ra)
asia.predictors3 <- mask(asia.predictors,ra)
于 2015-12-25T09:18:56.390 回答