10 REM "EXCENT5"
20 PI = 4 * ATN(1): k = 180 / PI: CLS : SCREEN 12
21 INPUT "ANNEE DE DEPART "; AN0: INPUT "ANNEE DE FIN "; AN1
22 CLS : LINE (650, 30)-(0, 30)
23 FOR AN = AN0 TO AN1 STEP 10000
24 PSET (10 + (AN - AN0) / ((AN1 - AN0) / 500) * 1.108, 25)
25 LINE -(10 + (AN - AN0) / ((AN1 - AN0) / 500) * 1.108, 35): NEXT AN
27 LINE (650, 170)-(0, 170): LINE (10, 20)-(10, 320)
28 PSET (10 + (0 - AN0) / ((AN1 - AN0) / 500) * 1.108, 2)
29 LINE -(10 + (0 - AN0) / ((AN1 - AN0) / 500) * 1.108, 320)
30 FOR Y = -.03 TO .03 STEP .01
31 LINE (0, 170 + 2000 * Y)-(10, 170 + 2000 * Y)
32 NEXT Y: PSET (10, 170)
35 XREF = 1: AN = 2000: kk = 0: GOSUB 70: XREF = XPOINT
40 kk = 1: PLUS = 0: MOINS = 0: FOR AN = AN0 TO AN1 STEP 1000
45 GOSUB 70: NEXT AN
50 LOCATE 19, 20
51 PRINT "Evolution climatique de l'an "; AN0; " … l'an "; AN1
60 LOCATE 21, 20
61 PRINT "ann‚es plus froides que maintenant "; MOINS * 1000
62 LOCATE 22, 20
63 PRINT "ann‚es plus chaudes que maintenant "; PLUS * 1000
64 END
70 IE = (23.2916667# + 1.308333 * COS(2 * PI * AN / 41000 + 1.151750966#))
71 IE = IE / k
72 ES = .0265 + .0265 * COS(2 * PI * AN / 100000 + 1.82397012#)
75 PREC = 2 * PI * AN / 25816.73 - 2 * PI * (AN - 2000) / 21000 + 1.313108
80 IF PREC < 0 THEN PREC = PREC + 2 * PI: GOTO 80
82 IF PREC > 2 * PI THEN PREC = PREC - 2 * PI: GOTO 82
85 LPS = ATN(TAN(PREC / 2) * SQR((1 + ES) / (1 - ES)))
87 IF COS(PREC / 2) < 0 THEN LPS = LPS + PI
88 LPS = LPS * 2
90 IF LPS > 2 * PI THEN LPS = LPS - 2 * PI: GOTO 90
95 IF LPS < 0 THEN LPS = LPS + 2 * PI: GOTO 95
150 AAS = 1.00000101778#: SELL = PI * AAS * AAS * SQR(1 - ES * ES)
160 TETA0 = PI / 2 - LPS: CSTE = 365.25 / PI / AAS / AAS / SQR(1 - ES * ES)
162 IF TETA0 < 0 THEN TETA0 = 2 * PI + TETA0: GOTO 162
163 IF TETA0 > 2 * PI THEN TETA0 = -2 * PI + TETA0: GOTO 163
170 TETA = TETA0
175 DISTDH = AAS * (1 - ES * ES) / (1 + ES * COS(TETA))
178 GOSUB 300: S0 = S
180 TETA = TETA0 + PI / 2
183 IF TETA > 2 * PI THEN TETA = TETA - 2 * PI: GOTO 183
184 IF TETA < 0 THEN TETA = TETA + 2 * PI: GOTO 184
185 GOSUB 300: S1 = S: IF S1 < S0 THEN S1 = S1 + SELL
190 SHIV = S1 - S0
200 DHIV = SHIV * CSTE
205 DISTFH = AAS * (1 - ES * ES) / (1 + ES * COS(TETA))
210 TETA = TETA + PI / 2
213 IF TETA > 2 * PI THEN TETA = TETA - 2 * PI: GOTO 213
214 IF TETA < 0 THEN TETA = TETA + 2 * PI: GOTO 214
215 GOSUB 300: S2 = S: IF S2 < S1 THEN S2 = S2 + SELL
220 SPRI = S2 - S1
230 DPRI = SPRI * CSTE
235 DISTFP = AAS * (1 - ES * ES) / (1 + ES * COS(TETA))
240 TETA = TETA + PI / 2
243 IF TETA > 2 * PI THEN TETA = TETA - 2 * PI: GOTO 243
244 IF TETA < 0 THEN TETA = TETA + 2 * PI: GOTO 244
245 GOSUB 300: S3 = S: IF S3 < S2 THEN S3 = S3 + SELL
250 SETE = S3 - S2
260 DETE = SETE * CSTE
265 DISTFE = AAS * (1 - ES * ES) / (1 + ES * COS(TETA))
270 TETA = TETA + PI / 2
273 IF TETA > 2 * PI THEN TETA = TETA - 2 * PI: GOTO 273
274 IF TETA < 0 THEN TETA = TETA + 2 * PI: GOTO 274
275 GOSUB 300: S4 = S: IF S4 < S3 THEN S4 = S4 + SELL
280 SAUT = S4 - S3
285 DAUT = SAUT * CSTE: DISTFA = AAS * (1 - ES * ES) / (1 + ES * COS(TETA))
286 XPOINT = 1
290 XPOINT = XPOINT * SQR((DAUT + DHIV) / 182.625)
292 XPOINT = XPOINT * COS(IE) / COS(.4065162#)
295 IF XPOINT < XREF THEN PLUS = PLUS + 1 ELSE MOINS = MOINS + 1
296 pp1 = 10 + (AN - AN0) / ((AN1 - AN0) / 500) * 1.108
297 IF kk = 1 THEN LINE -(pp1, 170 + 2000 * (XPOINT - 1))
298 RETURN
300 FC = 2 * ATN(SQR((1 - ES) / (1 + ES)) * TAN(TETA / 2))
305 IF FC < 0 THEN FC = FC + 2 * PI
310 S = AAS * AAS * SQR(1 - ES * ES) / 2 * (FC - ES * SIN(FC))
320 RETURN