100 REM "CALCULATING PI FOR HUNDREDS OF DIGITS" 110 REM "THX TO ROSETTACODE.ORG FOR THE BASE OF THE PROGRAM" 120 REM "SHOULD BE A BENCHMARK FOR THE BASIC INTERPRETER/COMPILER" 130 REM "WRITTEN IN 2023 FOR FORUM.CLASSIC-COMPUTING.DE BY PETER DASSOW" 135 REM "Ported to IoT BASIC by Guido Lehwalder" 136 REM "Added some IoT BASIC features - Stefan Lenz, 2023" 137 CLS 140 PRINT "Calculating Pi as a BASIC benchmark." 150 PRINT "Enter number of digits: "; 160 INPUT S$ 170 IF S$="" THEN PRINT "Nothing done.": END 180 N=VAL(S$): IF N<1 THEN PRINT "Not a valid number.": GOTO 150 190 REM "N DETERMINES ALSO THE ARRAY (ABOUT 3-4 TIMES BIGGER)" 200 LN=INT(10*N/3)+16 204 REM "@ is the space on the heap for numbers, reserve 64 bytes" 205 IF LN>(@-64) THEN PRINT "Not enough memory": GOTO 150 210 ND=1 220 SM=MILLIS(1) 225 REM "Delete the array if already there" 230 IF FIND(A())<>0 THEN CLR A() 235 REM "Then redim" 240 DIM A(LN) 250 N9=0 260 PD=0 270 REM 280 FOR J=1 TO LN 290 A(J)=2 300 NEXT J 310 REM "Use of the modulo operator % speeds things up" 320 FOR J=1 TO N 330 Q=0 340 FOR I=LN TO 1 STEP -1 350 X=10*A(I)+Q*I 360 A(I)=X%(2*I-1) 370 Q=INT(X/(2*I-1)) 380 NEXT I 390 A(1)=Q%10 400 Q=INT(Q/10) 410 IF Q=9 THEN N9=N9+1: GOTO 610 420 IF Q<>10 THEN GOTO 540 430 REM "Q==10" 440 D=PD+1: GOSUB 670 450 IF N9<=0 THEN GOTO 500 460 FOR K=1 TO N9 470 D=0: GOSUB 670 480 NEXT K 490 REM "END IF" 500 PD=0 510 N9=0 520 GOTO 610 530 REM "Q<>10" 540 D=PD: GOSUB 670 550 PD=Q 560 IF N9=0 THEN GOTO 610 570 FOR K=1 TO N9 580 D=9: GOSUB 670 590 NEXT K 600 N9=0 610 NEXT J 620 C$=("0"+PD%10) 621 PRINT C$ 630 EM=MILLIS(1)-SM 635 PRINT "Calculation time ";EM/1000;" seconds." 640 GOTO 140 650 REM 660 REM "OUTPUT DIGITS" 670 C$=("0"+D%10) 671 IF ND=0 THEN PRINT C$;: RETURN 680 IF D=0 THEN RETURN 691 PRINT C$;"."; 700 ND=0 710 RETURN