[expr] "raise to power" operator, similar to [pow] function Returns an integer value if both arguments are integers, and [double]-precision floating-point otherwise. The left operand may be any integer from Tcl's unlimited integer range. The right operand is limited to a max integer value of 268435455 (0xfffffff) (28 bits). (Unless the left operand is -1, 0, or 1, so that the answer is trivial). Expect to wait a long while for [[expr 2**0xfffffff]] to return. During early 2009, a thread broke out in the comp.lang.tcl usenet group discussing the observation that Tcl's calculation for ====== puts [expr {-2**2}] ====== surprised someone who was expecting the same results as algebra (or even [perl]). Instead of the results being '''-4''' , Tcl returns '''4'''. The reason has to do with the operator precendence between the [-] and '''**''' operators. [ZB] Either I can't count - feel free to correct me in such case - or indeed TCL is right: (-2)^2 = (-2)*(-2) = 4 Why such "surprise"? ---- !!!!!! %|[Category Operator]|[Category Command]|[Category Mathematics]|% !!!!!!