10 REM Table of Quarter Squares 20 CLEAR :CLS :KEY OFF 30 PRINT,,"QUARTER SQUARES" :PRINT 40 PRINT "Before the discovery of logarithms, tables of quartersquares were used" 50 PRINT "for multiplication. The quartersquare of an integer is the integer part" 60 PRINT "of one quarter of its square." :PRINT 70 PRINT "To multiply the two numbers x and y it is simply necessary to calculate" 80 PRINT,"xy = quartersquare(x+y) - quartersquare(x-y)" :PRINT 90 PRINT "Press any key for a sample table of quartersquares of integers up to 199." 100 GOSUB 260 'PRESS ANY KEY 110 PRINT TAB(13); 120 FOR UNIT = 0 TO 9 130 PRINT USING "######";UNIT; 140 NEXT UNIT 150 PRINT :PRINT 160 FOR TENS = 0 TO 190 STEP 10 170 PRINT TAB(8); USING "####";TENS; 180 PRINT " "; 190 FOR NUMBER = TENS TO TENS+9 200 PRINT USING "######"; INT(NUMBER^2/4); 210 NEXT NUMBER 220 PRINT 230 NEXT TENS 240 END 250 ' ---------------------------------------------- 260 ' PRESS ANY KEY 270 ' ---------------------------------------------- 280 LOCATE 25,1 :PRINT ,,,"Press any key to continue"; 290 WHILE INKEY$ = "" :WEND 300 CLS 310 RETURN |