# remove.projections: Identify candidate points making up all marginal... In demu: Optimal Design Emulators via Point Processes

## Description

`remove.projections()` is a helper function to identify all lower-dimensional marginal projection points of the existing design points indexed by `curpts`. This function can be used to remove a subset of points from the candidate set in order to enforce non-collapsingness of when sequentially adding design points.

## Usage

 `1` ```remove.projections(curpts,X) ```

## Arguments

 `curpts` Indices of points currently in the design `X` An `n x p` matrix of all candidate points

## Value

A list containing the vector `curpts`, the vector `projpts` which contains the identified projection points of the current design, and `allpts`.

`demu-package` `sim.dpp.modal.seq`
 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21``` ```library(demu) n1=3 n2=3 n3=3 rho=rep(1e-10,2) ngrid=10 x=seq(0,1,length=ngrid) X=as.matrix(expand.grid(x,x)) l.d=makedistlist(X) # Initial design R=rhomat(l.d,rho)\$R pts.1=sim.dpp.modal(R,n1) pts.1.proj=remove.projections(pts.1,X) # Plot - design points in black, design+projection points in grey. #plot(X,xlim=c(0,1),ylim=c(0,1)) #points(X[pts.1.proj\$projpts,],pch=20,cex=2,col="grey") #points(X[pts.1,],pch=20,cex=2) ```