/* * call-seq: * dvector.atan -> a_dvector * * Returns of copy of _dvector_ with entry x replaced by atan(x). * * a = Dvector[ 0.1, -0.2, -0.3, 0.4 ] * a.atan -> Dvector[ atan(0.1), atan(-0.2), atan(-0.3), atan(0.4) ] */ VALUE dvector_atan(VALUE ary) {