Wayne.MJ
69 lines
1.9 KiB
COBOL
69 lines
1.9 KiB
COBOL
IDENTIFICATION DIVISION.
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* A rewrite of a fortran program that is rewrite of a REXX script
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* to find the square root of a number
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PROGRAM-ID. SQRNEWT.
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AUTHOR. Wayne.
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DATA DIVISION.
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WORKING-STORAGE SECTION.
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01 WORK-AREA.
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05 MAX-ITER PIC 9(3) VALUE 100.
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05 ITER PIC 9(3).
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05 TOL PIC 9(3)V9(12) VALUE 0.0000000001.
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05 RR PIC S9(3)V9(12).
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05 R PIC S9(3)V9(12).
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05 N PIC S9(3)V9(12).
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05 N-TEXT PIC X(15).
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05 DIS-RESULTS PIC Z(3).9(12).
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PROCEDURE DIVISION.
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DISPLAY "Enter a 3 digit value <> 0:"
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* ACCEPT N FROM PARMS
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* MOVE 4 TO N
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ACCEPT N-TEXT
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PERFORM VALID-INPUT
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STOP RUN.
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* Validate the input
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* If less than 0 ie negative, make it positive
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* If 0 then drop out
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VALID-INPUT.
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INSPECT N-TEXT REPLACING ALL "," BY "."
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COMPUTE N = FUNCTION NUMVAL(N-TEXT)
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* DISPLAY N
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IF N LESS THAN ZERO THEN
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COMPUTE N = N * (- 1)
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DISPLAY "CORRECTED FOR NEGATIVE VALUE"
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END-IF.
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IF N NOT EQUAL ZERO THEN
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PERFORM FIND-SQRROOT
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ELSE
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DISPLAY "CANNOT BE ZERO"
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END-IF.
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END-VALID-INPUT.
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* Find the SQR Root of a number
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FIND-SQRROOT.
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MOVE 0 to ITER
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MOVE 1 to R
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PERFORM UNTIL ITER GREATER OR EQUAL MAX-ITER
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COMPUTE ITER = ITER + 1
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COMPUTE RR = (N / R + R) / 2
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IF (FUNCTION ABS(RR - R) <= TOL) THEN
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EXIT PERFORM
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END-IF
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MOVE RR TO R
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END-PERFORM
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MOVE RR TO DIS-RESULTS
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DISPLAY DIS-RESULTS.
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END-FIND-SQRROOT.
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