FPATAN            Partial Arctangent          Exception Flags: U P

FPATAN

       Logic:      T1 . ARCTAN(ST(1)/ST)
                   pop stack
                   ST . T1

     FPATAN finds the partial artangent of ST(1)/ST. On the 8087 and
     80287, ST and ST(1) must be in the limits 0 . ST(1) < ST . .. There
     is no restriction on ST(1) or ST on the 80387. The partial
     arctangent is left in ST.

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   Operands            Clocks         Bytes           Example
   FPATAN              250-800          3             FPATAN
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