##### evaluate exists 0<i<=length(x) x[i]%%2==0 E=function(x){ E=FALSE if (is.vector(x)&& is.numeric(x)){ for(i in 1:length(x)){ E=(x[i]%%2==0 || E) } } return(E) } x=c(1,2,3) E(x) x=c(1,5,3) E(x) any(x%%2==0) ##### evaluate for all 0<i<=length(x) x[i]%%2==0 A=function(x){ A=TRUE if (is.vector(x)&& is.numeric(x)){ for(i in 1:length(x)){ A=(x[i]%%2==0 && A) } } return(A) } x=c(1,2,3) A(x) x=c(2,4,12) A(x) all(x%%2==0) ##### evaluate exists 0<i<=nrow(m) s.t. for all 0<j<=ncol(m) m[i,j]%%2==0 EA=function(m){ E=FALSE if (is.matrix(m)&& is.numeric(m)){ for(i in 1:nrow(m)){ A=TRUE for (j in 1:ncol(m)) A=(m[i,j]%%2==0 && A) E=E||A } } return(E) } debug(EA) m=matrix(c(1,3,3,4),ncol=2) EA(m) m=matrix(c(1,2,6,4),ncol=2) EA(m) ##### evaluate for all 0<i<=nrow(m) exists 0<j<=ncol(m) s.t. m[i,j]%%2==0 AE=function(m){ A=TRUE if (is.matrix(m)&& is.numeric(m)){ for(i in 1:nrow(m)){ E=FALSE for (j in 1:ncol(m)) E=(m[i,j]%%2==0 || E) A=A && E } } return(A) } debug(AE) m=matrix(c(1,3,2,4),ncol=2) AE(m) m=matrix(c(1,2,1,4),ncol=2) AE(m)