ecospat.recstrat_prop {ecospat} R Documentation

## Random Ecologically Stratified Sampling of propotional numbers

### Description

This function randomly collects a user-defined total number of samples from the stratification layer.

### Usage

  ecospat.recstrat_prop(in_grid, sample_no)


### Arguments

 in_grid The stratification grid to be sampled. sample_no The total number of pixels to be sampled.

### Details

The number of samples per class are determined proportional to the abundance of each class. The number of classes in the stratification layer are determined automatically from the integer input map. If the proportion of samples for a certain class is below one then no samples are collected for this class.

### Value

Returns a dataframe with the selected sampling locations their coordinates and the strata they belong in.

### Author(s)

Achilleas Psomas achilleas.psomas@wsl.ch and Niklaus E. Zimmermann niklaus.zimmermann@wsl.ch

ecospat.recstrat_regl ecospat.rcls.grd

### Examples

    library(raster)
library(classInt)

bio3<- raster(system.file("external/bioclim/current/bio3.grd",package="biomod2"))
bio12<- raster(system.file("external/bioclim/current/bio12.grd",package="biomod2"))

B3.rcl<-ecospat.rcls.grd(bio3,9)
B12.rcl<-ecospat.rcls.grd(bio12,9)
B3B12.comb <- B12.rcl+B3.rcl*10

B3B12.prop_samples <- ecospat.recstrat_prop(B3B12.comb,100)

plot(B3B12.comb)
points(B3B12.prop_samples$x,B3B12.prop_samples$y,pch=16,cex=0.6,col=B3B12.prop_samples\$class)


[Package ecospat version 3.4 Index]