Howdy fellow Boosters! i've been using the BGL for quite some time now (as for implementing my own version of a critical path estimator on DAGs with weighted nodes). While i was searching for general software on "interval arithmetic" out there, i luckily found out (although i feel much more confident in C) that Boost has its own interval library supporting integers (which is what i'm mostly interested in). My question is if it is meaningful (it is for the analysis in mind:) to implement a SELECT operator that works on intervals. The SELECT operation would be: -> src1, if cond!=0 dst <= | | -> src2, if cond=0 In C trigraph notation this would be dst = (cond?src1:src2); To my understanding, the equivalent in interval arithmetic would be either transfer the interval associated with src1 variable to the dst, or the one associated with src2, depending on the cond (probably a degenerate interval of the form [C,C]. In my problem, the SELECT operator expresses data dependencies (actually it is the result of converting from control to data dependence). Is it possible, to check interval propagation not only on polynomials but on sequences featuring such SELECT interval operators? Or better, is it already there, build in the "interval" numeric sublibrary? Thanks in advance Nikolaos Kavvadias