| 1 | / |
| 2 | / |
| 3 | / A L O G |
| 4 | / - - - - |
| 5 | / |
| 6 | /SUBROUTINE ALOG(X) |
| 7 | / |
| 8 | / VERSION 5A 4-26-77 (MH) |
| 9 | / |
| 10 | SECT ALOG |
| 11 | JA #ALOG |
| 12 | 0 /WORKING SPACE FOR EXPONENT DIDDLE. |
| 13 | 0 |
| 14 | 0 |
| 15 | ALOGTM, 0 |
| 16 | 0 |
| 17 | 0 |
| 18 | 0 |
| 19 | F2ALOG, F 2. |
| 20 | FPI2, 1 |
| 21 | 3110 |
| 22 | 3755 |
| 23 | / |
| 24 | EXTERN #ARGER |
| 25 | ALOG0, TRAP4 #ARGER |
| 26 | JA ALGRTN /RETURN NOW. |
| 27 | / |
| 28 | EXTERN #ARGER |
| 29 | ALOGM1, TRAP4 #ARGER |
| 30 | JA ALGRTN |
| 31 | TEXT +ALOG + |
| 32 | ALOGXR, |
| 33 | BPALOG, F 0.0 |
| 34 | XRALOG, F 0.0 |
| 35 | ALOG1, F 0.0 |
| 36 | ALOG2, F 0.0 |
| 37 | F1ALOG, F 1. |
| 38 | / |
| 39 | ALOGMG, 0 |
| 40 | 0 |
| 41 | 13 /CORRECT EXPONENT DIDDLER. |
| 42 | / |
| 43 | / |
| 44 | / |
| 45 | / |
| 46 | ALOGL1, 0 |
| 47 | 3777 |
| 48 | 7742 |
| 49 | / |
| 50 | ALOGE2, 0 |
| 51 | 2613 |
| 52 | 4414 |
| 53 | / |
| 54 | ORG 10*3+BPALOG |
| 55 | FNOP |
| 56 | JA ALOGXR |
| 57 | 0 |
| 58 | ALGRTN, JA . |
| 59 | ALOGL2, 7777 |
| 60 | 4000 |
| 61 | 4100 |
| 62 | / |
| 63 | ALOGL3, 7777 |
| 64 | 2517 |
| 65 | 0310 |
| 66 | / |
| 67 | ALOGL4, 7776 |
| 68 | 4113 |
| 69 | 7211 |
| 70 | / |
| 71 | ALOGL5, 7776 |
| 72 | 2535 |
| 73 | 3301 |
| 74 | / |
| 75 | ALOGL6, 7775 |
| 76 | 4746 |
| 77 | 0771 |
| 78 | / |
| 79 | ALOGL7, 7774 |
| 80 | 2236 |
| 81 | 4304 |
| 82 | / |
| 83 | ALOGL8, 7771 |
| 84 | 4544 |
| 85 | 1735 |
| 86 | BASE 0 |
| 87 | #ALOG, STARTD |
| 88 | FLDA 10*3 |
| 89 | FSTA ALGRTN |
| 90 | FLDA 0 |
| 91 | SETX XRALOG |
| 92 | SETB BPALOG |
| 93 | BASE BPALOG |
| 94 | LDX 1,1 |
| 95 | FSTA BPALOG |
| 96 | FLDA% BPALOG,1 /ADDR OF X |
| 97 | FSTA BPALOG |
| 98 | STARTF |
| 99 | FLDA% BPALOG /GET X |
| 100 | JEQ ALOG0 /IF =0 THEN ERROR |
| 101 | JLT ALOGM1 /IF<0 THEN ERROR |
| 102 | LDX -1,0 /IF >0 THEN START DOING |
| 103 | FSTA ALOG1 /SAVE IN A TEMP. |
| 104 | FSUB F1ALOG /KNOCK OFF ONE. |
| 105 | JEQ ALGRTN /IF ZERO EXIT. LOG(1)=0 |
| 106 | JGE ALOGST /IF POSITIVE LOG>0 |
| 107 | FLDA F1ALOG /NEGITE. INVERT IT. |
| 108 | FDIV ALOG1 /BY DIVIDING INTO ONE. |
| 109 | FSTA ALOG1 |
| 110 | LDX 0,0 /RESET SIGN TO NEGATIVE. |
| 111 | JA .+3 /AVOID USELESS LOAD INSTRUCTION. |
| 112 | / |
| 113 | ALOGST, FLDA ALOG1 /RECALL NUMBER. |
| 114 | FDIV F2ALOG /CUT IN HALF. |
| 115 | FSTA ALOGTM /PREPARE FOR EXPONENT DIDDLE. |
| 116 | FLDA ALOGMG /SET THE EXPONENT OF THE EXPONENT TO 13. |
| 117 | FSTA ALOGTM-3 /SO THAT NORMALIZE WILL DO JOB. |
| 118 | FSTA ALOGTM+1 /AND ALSO ZERO OUT LOW ORDER POART OF EX. MANT. |
| 119 | FLDA ALOGTM-1 /RECALL THE NUMBER |
| 120 | FNORM /NORMALIZE IT. |
| 121 | FMUL ALOGE2 /NOW MULITPLY EXPONENT BY LOG E 2 |
| 122 | FSTA ALOG2 /AND SAVE IT FOR A SECOND. |
| 123 | FLDA ALOG1 /RECALL THE NUMBER AGAIN. |
| 124 | FSTA ALOGTM /STORE IN THE TEMPORARY WORKER. |
| 125 | FLDA FPI2-2 /RECALL WORD WITH LOW ORDER ONE. |
| 126 | FSTA ALOGTM-2 /STORE AWAY. |
| 127 | FLDA ALOGTM /RECALL NUMBER WITH AN EXPONENT OF 1 |
| 128 | FSUB F1ALOG /SUBTRACT AWAY. |
| 129 | FSTA ALOG1 /AND STORE |
| 130 | FMUL ALOGL8 /MULTIPLY BY THE CONSTANT. |
| 131 | FADD ALOGL7 /ADD IN |
| 132 | FMUL ALOG1 /MULT. |
| 133 | FADD ALOGL6 /AND SO ON DOWN THE LINE. |
| 134 | FMUL ALOG1 |
| 135 | FADD ALOGL5 |
| 136 | FMUL ALOG1 |
| 137 | FADD ALOGL4 |
| 138 | FMUL ALOG1 |
| 139 | FADD ALOGL3 |
| 140 | FMUL ALOG1 |
| 141 | FADD ALOGL2 |
| 142 | FMUL ALOG1 |
| 143 | FADD ALOGL1 |
| 144 | FMUL ALOG1 |
| 145 | FADD ALOG2 /CORRECT NOW.ADD IN EXPONENT. |
| 146 | JXN ALGRTN,0 /EXIT IF SIGN IS OK. |
| 147 | FNEG /ELSE NEGATE IT. |
| 148 | JA ALGRTN |
| 149 | \f |