Problem with RegionFunction

*To*: mathgroup at smc.vnet.net*Subject*: [mg88031] Problem with RegionFunction*From*: zac <replicatorzed at gmail.com>*Date*: Tue, 22 Apr 2008 06:28:53 -0400 (EDT)

Dear Group, any idea what is the problem with the output of this Manipulate? Manipulate[ Plot3D[Sin[x]*Cos[y],{x,1,10},{y,2,10},RegionFunction->Function[{x,y}, 45<=(y^x)]] ,{dummy,{True,False}}] Interestingly none of the following codes produces errors: Plot3D[Sin[x]*Cos[y], {x, 1, 10}, {y, 1, 10}, RegionFunction -> Function[{x, y}, 45 <= (y^x)]] Manipulate[ Plot3D[Sin[x]*Cos[y], {x, 1, 10}, {y, 1, 10}, RegionFunction -> If[region, All, Function[{x, y}, 45 <= (y^x)]]] , {region, {True, False}}] Any suggestion would be appreciated. Thanks in advance, Istvan Zachar