... Version 0.5.4 1) polycount has a few bugs for very small problem (i.e. 2 lines in R2, or all lines are parallel). An error message will be thrown if users try to use polycount for arrangement with dim > 2. 2) NICERd: added an option to turn off acceleration. If hyperplanes are not in general position, an error will be thrown to tell user to turn off acceleration. This is a temporary measure, at the end of the day, would like to figure out a way to accelerate even when hyperplanes are degenerate (ie. all through origin, or less extreme). 3) NICER: intended to be used for dim = 2, now will throw an error if user feed in hyperplanes of dim > 2. Same with polyzone, which is also constructed for dim = 2. 4) Added a demo on arrangement for dim = 2. Version 0.5.5 1) witness function: seems there is a mosek bug. Try the following problem, mosek gives optimal answer (0,0,0), while (-2,1,1) is clearly giving a larger objective value. Interior = list() Interior$sense = "max" Interior$c = c(0,0,1) blx = c(-Inf,-Inf,0) bux = c(Inf,Inf,1) Interior$bx = rbind(blx, bux) S = diag(c(-1,1,1)) A0 = cbind(c(1,0,-1),c(0,1,-1)) A = cbind(S%*%A0, matrix(-1,3,1)) Interior$A = Matrix(A, sparse=TRUE) buc = c(rep(Inf,3)) blc = c(rep(0,3)) Interior$bc = rbind(blc, buc) r = mosek(Interior) Fix (Mosek responded that it is indeed a bug for Mosek 7 and 8 (not for Mosek 9), email correspondence Sept 28,2020) and suggested changing Interior$A = as(A, 'dgCMatrix'). 0.6.1 1. Fixed packageVersion problem as suggested by Kurt. 2. Reduced dimension of example for rcbr to comply with CRAN time limits.