/*
 *  call-seq:
 *     dtable.set_row(int,a_dvec) -> a_dvec
 *  
 *  Stores the contents of _a_dec_ in the specified row of the array.
 *  The length of the vector must equal the number of columns in the array.
 */ VALUE dtable_set_row(VALUE ary, VALUE row_num, VALUE dvec) {