## Don't show: data(thermo)thermo$obigt: 1809 aqueous, 3368 total species## End(Don't show) ## properties of phase transitions si <- info("enstatite")info.character: found enstatite(cr1), also available in cr2, cr3# (dP/dT) of transitions dPdTtr(si) # first transition[1] 384.5063dPdTtr(si+1) # second transition[1] 11.90108# temperature of transitions (Ttr) as a function of P Ttr(si,P=c(1,10,100,1000))[1] 903.0026 903.0260 903.2601 905.6007Ttr(si,P=c(1,10,100,1000))[1] 903.0026 903.0260 903.2601 905.6007## scale logarithms of activity # suppose we have two proteins whose lengths are 100 and # 200; what are the logarithms of activity of the proteins # that are equal to each other and that give a total # activity of residues equal to unity? logact <- c(-3,-3) # could be any two equal numbers length <- c(100,200) logact.tot <- 0 loga <- unitize(logact,length,logact.tot) # the proteins have equal activity stopifnot(identical(loga[1],loga[2])) # the sum of activity of the residues is unity stopifnot(isTRUE(all.equal(sum(10^loga * length),1))) ## now, what if the activity of protein 2 is ten ## times that of protein 1? logact <- c(-3,-2) loga <- unitize(logact,length,logact.tot) # the proteins have unequal activity stopifnot(isTRUE(all.equal(loga[2]-loga[1],1))) # but the activities of residues still add up to one stopifnot(isTRUE(all.equal(sum(10^loga * length),1)))