/* * call-seq: * dvector.sub(number) -> a_dvector * dvector.sub(other) -> a_dvector * dvector - number -> a_dvector * number - dvector -> a_dvector * dvector - other -> a_dvector * * When argument is a number, this operation returns a copy of _dvector_ with each entry x replaced by x - _number_. * When argument is a vector, this operation returns a copy of _dvector_ with each entry x replaced * by x - the corresponding entry in the _other_ vector. * * a = Dvector[ 11, -5, 2 ] * a.sub(3) -> Dvector[ 8, -8, -1 ] * a - 3 -> Dvector[ 8, -8, -1 ] * 3 - a -> Dvector[ -8, 8, 1 ] * b = Dvector[ 7, 4, -10 ] * a.sub(b) -> Dvector[ 4, -9, 12 ] * a - b -> Dvector[ 4, -9, 12 ] */ VALUE dvector_sub(VALUE ary, VALUE arg) {