1 /* ******************************************************
 2    *                                                    *
 3    *                                                    *
 4    * Copyright (c) 1972 by Massachusetts Institute of   *
 5    * Technology and Honeywell Information Systems, Inc. *
 6    *                                                    *
 7    *                                                    *
 8    ****************************************************** */
 9 
10 clog_: proc (number) returns (complex float bin (27));
11 
12 dcl (number, a, b) complex float bin (27);
13 
14 dcl  code_ ext entry (fixed bin (17)),
15           (abs, atan, imag, log, real) builtin;
16 
17           a = number;
18 
19           if a = 0.0e0
20                then do;
21                call code_ (28);
22                return (-170141182.0e30);
23           end;
24 
25           imag (b) = atan(imag (a), real (a));
26           real (b) = log (abs (a));
27 
28           return (b);
29 
30      end clog_;