       .TITLE ATAN   COMPUTE ARCTANGENT FOR REAL ARGUMENT
/ 
/ 
/                   FIRST PRINTING, FEBRUARY 1974
/ 
/ THE INFORMATION IN THIS DOCUMENT IS SUBJECT TO 
/ CHANGE WITHOUT NOTICE AND SHOULD NOT BE CONSTRUED
/ AS A COMMITMENT BY DIGITAL EQUIPMENT CORPORATION.
/ DIGITAL EQUIPMENT CORPORATION ASSUMES NO RESPON-
/ SIBILITY FOR ANY ERRORS THAT MAY APPEAR IN THIS
/ DOCUMENT.
/ 
/ THE SOFTWARE DESCRIBED IN THIS DOCUMENT IS FUR-
/ NISHED TO THE PURCHASER UNDER A LICENSE FOR USE ON
/ A SINGLE COMPUTER SYSTEM AND CAN BE COPIED (WITH
/ INCLUSION OF DIGITAL'S COPYRIGHT NOTICE) ONLY FOR 
/ USE IN SUCH SYSTEM, EXCEPT AS MAY OTHERWISE BE PRO-
/ VIDED IN WRITING BY DIGITAL.
/ 
/ DIGITAL EQUIPMENT CORPORATION ASSUMES NO RESPONSIBILITY
/ FOR THE USE OR RELIABILITY OF ITS SOFTWARE ON EQUIP-
/ MENT THAT IS NOT SUPPLIED BY DIGITAL.
/ 
/ COPYRIGHT (C) 1974, BY DIGITAL EQUIPMENT CORPORATION
/ 
/ 
        .EJECT
/COPYRIGHT 1970,1971, DIGITAL EQUIPMENT CORP., MAYNARD, MASS. 01754
/FOR HARDWARE FLOATING POINT PROCESSOR (FPP), DEFINE 90 FPP,
/EDIT 2   1-26-71
       .GLOBL ATAN,.DA,.ED
	.IFUND %FPP
	.GLOBL .AG
	.ENDC
	.IFUND %FPP
	.DEFIN FLD%,A		/FLOATING LOAD (.AG)
	JMS* A
	.ENDM
	.ENDC
	.IFDEF %FPP
FLD=713050
	.DEFIN FLD%
	FLD
	.ENDM
	.ENDC
/             CALLING SEQUENCE
/      JMS*   (ATAN)          SUBR CALL
/      JMP    .+2             SUBR RETURN
/      CAL/XCTADDR            ADDR OF ARGUMENT (XCT IF INDIRECT)
/
ATAN   CAL    0              /ENTRY-EXIT
       JMS*   .DA            /GET ARGUMENT (.DA)
       JMP    ATAN02
ATAN01 CAL    0              /ARGUMENT
ATAN02 FLD%   .AG            /LOAD REAL (.AG)
       .DSA   ATAN01+400000  / (ARG)
       JMS*   .ED            /COMPUTE ARCTANGENT (.ED)
       JMP*   ATAN           /EXIT
       .END
