1000 PRINT "FINDS AVERAGES OF TWO SETS OF NUMBERS, STANDARD" 1100 PRINT "DEVIATION FOR A GIVEN NUMBER OF X,Y PAIRS." 1200 PRINT "LISTS SUMS OF X, X SQUARED, Y, Y SQUARED AND" 1300 PRINT "SUM OF XY, AS STORED IN A SET OF REGISTERS 'R(N)'." 1400 PRINT "CALCULATES SLOPE AND INTERCEPT FOR LINEAR DIGRESSION." 1500 PRINT 1600 PRINT "FIRST ASKS WHETHER A NEW SET OF X,Y PAIRS IS TO BE" 1700 PRINT "ENTERED OR A CHANGE IS DESIRED IN ONE OF THE PAIRS" 1800 PRINT "ALREADY ENTERED." 1900 PRINT "THEN, EACH OF THE 'N' X,Y PAIRS IS REQUESTED. WHEN" 2000 PRINT "THE LAST PAIR IS ENTERED, THE RESULT IS DISPLAYED." 2100 PRINT 2200 PRINT "IF 'C' IS CHOSEN, IT ASKS WHETHER YOU WANT A NUMBERED" 2300 PRINT "LIST OF PAIRS. THEN ASKS WHICH ENTRY YOU WANT TO CHANGE." 2400 PRINT "THE MODIFIED LIST IS USED TO RE-CALCULATE." 2500 PRINT 2600 COMMON 2700 PRINT "ENTER 'N' FOR NEW VALUES OR 'C' TO CHANGE A VALUE"; 2800 INPUT W$ 2900 IF W$ = "N" THEN 3200 3000 IF W$ = "C" GOSUB 7400 3100 GOTO 4700 3200 EXPUNGE 3300 PRINT "INPUT NUMBER OF PAIRS:"; 3400 INPUT N 3500 LET N2 = N 3600 DIM X(N) 3700 DIM Y(N) 3800 DIM R(5) 3900 PRECISION 11 4000 FOR C = 1 TO N 4100 PRINT "INPUT: X";C;",Y";C 4200 INPUT X,Y 4300 LET X(C) = X 4400 LET Y(C) = Y 4500 NEXT 4600 PRECISION 11 4700 FOR R = 1 TO 5 4800 LET R(R) = 0 4900 NEXT 5000 GOSUB 6600 5100 GOSUB 5400 5200 GOSUB 8600 5300 END 5400 FOR R = 1 TO 5 5500 PRINT "R(";R;") = ";R(R) 5600 NEXT 5700 PRINT 5800 PRINT "AVERAGE FOR X = ";R(1)/N 5900 PRINT "AVERAGE FOR Y = ";R(3)/N 6000 LET S1 = SQRT((N*R(2)-R(1)^2)/(N*(N-1))) 6100 LET S2 = SQRT((N*R(4)-R(3)^2)/(N*(N-1))) 6200 PRINT 6300 PRINT "STANDARD DEVIATION FOR X = ";S1 6400 PRINT "STANDARD DEVIATION FOR Y = ";S2 6500 RETURN 6600 FOR C = 1 TO N 6700 LET R(1) = R(1)+X(C) 6800 LET R(2) = R(2)+X(C)^2 6900 LET R(3) = R(3)+Y(C) 7000 LET R(4) = R(4)+Y(C)^2 7100 LET R(5) = R(5)+X(C)*Y(C) 7200 NEXT 7300 RETURN 7400 PRINT "LIST CURRENT VALUES? Y/N"; 7500 INPUT L$ 7600 IF L$ = "Y" GOSUB 8200 7700 PRINT "CHANGE VALUES FOR ELEMENT"; 7800 INPUT N2 7900 PRINT "NEW VALUES FOR X AND Y:"; 8000 INPUT X(N2),Y(N2) 8100 RETURN 8200 FOR C = 1 TO N 8300 PRINT "X(";C;") = ";X(C);" Y(";C;") = ";Y(C) 8400 NEXT 8500 RETURN 8600 PRINT 8700 PRINT "LINEAR REGRESSION SLOPE 'A' AND INTERCEPT 'B'" 8800 LET A = (N*R(5)-R(1)*R(3))/(N*R(2)-R(1)^2) 8900 LET B = (R(3)*R(2)-R(1)*R(5))/(N*R(2)-R(1)^2) 9000 PRINT "SLOPE A = ";A;" INTERCEPT B = ";B 9100 RETURN