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