Hi, The hyperbolic cosine function is off by a factor of 4 in the Clean 2.02 Linux distribution. The following program: module main import StdReal Start = (cosh (-1.4), cosh 1.4, 0.5 * (exp (-1.4) + exp 1.4)) gives (8.60359386157256,8.60359386157256,2.15089846539314) Sinh and tanh are OK. Regards, Gé Vissers