| | 1 | / |
| | 2 | / |
| | 3 | / |
| | 4 | / A T A N 2 |
| | 5 | / - - - - - |
| | 6 | / |
| | 7 | /SUBROUTINE ATAN2(Y,X) |
| | 8 | / |
| | 9 | / VERSION 5A 4-27-77 PT |
| | 10 | / |
| | 11 | SECT ATAN2 |
| | 12 | JA #ATAN2 |
| | 13 | TEXT +ATAN2 + |
| | 14 | ATN2XR, SETX XRATN2 |
| | 15 | SETB BPATN2 |
| | 16 | BPATN2, FNOP |
| | 17 | 0 |
| | 18 | 0 |
| | 19 | XRATN2, F 0.0 |
| | 20 | YCOR, F 0.0 |
| | 21 | XCOR, F 0.0 |
| | 22 | FPIAT2, 2 /PI |
| | 23 | 3110 |
| | 24 | 3755 |
| | 25 | ATPI, F 1.570796 /PI/2 |
| | 26 | ORG 10*3+BPATN2 |
| | 27 | FNOP |
| | 28 | JA ATN2XR |
| | 29 | 0 |
| | 30 | AT2RTN, JA . |
| | 31 | BASE 0 |
| | 32 | #ATAN2, STARTD |
| | 33 | FLDA 10*3 |
| | 34 | FSTA AT2RTN |
| | 35 | FLDA 0 |
| | 36 | SETX XRATN2 |
| | 37 | SETB BPATN2 |
| | 38 | BASE BPATN2 |
| | 39 | LDX 1,1 |
| | 40 | FSTA BPATN2 |
| | 41 | FLDA% BPATN2,1 /ADDR OF Y |
| | 42 | FSTA YCOR |
| | 43 | FLDA% BPATN2,1+ /ADDR OF X |
| | 44 | FSTA XCOR |
| | 45 | STARTF |
| | 46 | FLDA% YCOR /GET Y - THE TAN |
| | 47 | FSTA YCOR /SAV FOR A SECOND |
| | 48 | LDX 1,2 /POSITIVE X |
| | 49 | JEQ ATN0 |
| | 50 | JGT ATN1 |
| | 51 | LDX 0,2 |
| | 52 | ATN1, FLDA% XCOR /GET X - THE QUADRAND |
| | 53 | FSTA XCOR /+MOVE IT TO A SAFE PLACE |
| | 54 | JEQ ATASP |
| | 55 | FLDA YCOR /Y/X |
| | 56 | FDIV XCOR |
| | 57 | FSTA YCOR |
| | 58 | EXTERN ATAN |
| | 59 | JSR ATAN /CALL ATAN |
| | 60 | JA .+4 /TAKE ARCTAN OF Y/X |
| | 61 | JA YCOR |
| | 62 | FSTA YCOR /SAVE IT AWAY |
| | 63 | JGE A2 /SKIP IF 1 OR 3 Q |
| | 64 | FADD FPIAT2 /ADD PI FOR 4TH Q |
| | 65 | FSTA YCOR |
| | 66 | A2, JXN AT2RTN,2 |
| | 67 | FLDA YCOR |
| | 68 | FSUB FPIAT2 /SUB PI FOR 2ND+3RD QUADS |
| | 69 | JA AT2RTN |
| | 70 | ATASP, FLDA ATPI /X=0 MEANS +-PI/2 |
| | 71 | JXN ATNG,2 |
| | 72 | FNEG |
| | 73 | ATNG, JA AT2RTN |
| | 74 | ATN0, FLDA% XCOR |
| | 75 | JLT POSX /IF X POS,ANS IS 0 |
| | 76 | FCLA |
| | 77 | JA AT2RTN |
| | 78 | POSX, FLDA FPIAT2 /OTHERWISE,ANS IS PI |
| | 79 | JA AT2RTN |
| | 80 | \f |
projects / pdp8.git / blame_incremental