00001REM TUT9 00100PRINT"WELCOME TO LESSON 9. WE BRIEFLY INVESTIGATED THE TAPE UNIT LAST" 110PRINT"LESSON. HAVE YOU TRIED USING TAPE (YES OR NO)"; 120INPUT G$ 00130PRINT 140IF G$='NO' THEN 190 150 IF G$='YES' THEN 280 160PRINT "JUST 'YES' OR 'NO' WILL DO"; 180GOTO 120 00190PRINT"WELL, THAT SHOULD BE NEXT. DID YOU UNDERSTAND THE EXPLANATION" 00200PRINT"IN LESSON 8? I HOPE SO, BUT ACTUALLY TRYING IT SHOULD HELP YOU." 210PRINT"WOULD YOU LIKE TO TRY A SHORT TAPE NOW (YES OR NO)"; 220 INPUT R$ 00230PRINT 240IFR$='NO' THEN 400 250IF R$='YES'THEN1130 00260PRINT"YOU CAN'T ANSWER A 'YES OR NO' QUESTION THAT WAY. ONCE MORE -" 00270GOTO210 280PRINT"AND WERE YOU SUCCESSFUL"; 290INPUT B$ 00300PRINT 310IF B$='NO' THEN 350 320IF B$='YES'THEN 380 330PRINT"PLEASE TYPE 'YES' OR 'NO', WHICH"; 00340GOTO290 00350PRINT"IT MAY TAKE SOME PRACTICE BEFORE YOU GET PROFICIENT AT IT. YOU" 00360PRINT"PROBABLY SHOULD TRY AGAIN WHILE IT'S STILL FRESH IN YOUR MIND." 00370GOTO210 00380PRINT"THAT'S THE WAY TO DO IT. NOW I'D SAY IT WAS TIME WE WENT BACK" 00390GOTO410 00400PRINT"O.K. THEN - WE'LL FORGET ABOUT THE TAPE FOR AWHILE AND GO BACK" 00410PRINT"TO WRITING PROGRAMS. WE SAW THAT 'SQR' ALWAYS MEANS 'FIND THE" 00420PRINT"SQUARE ROOT'. WE REFER TO SUCH AN OPERATION AS A 'FUNCTION'." 00430PRINT 00440PRINT"THERE ARE MANY 'STANDARD' OR PREDEFINED FUNCTIONS, WHICH HAVE A" 00450PRINT"SET MEANING. 'SQR' IS ONE; 'LOG' IS ANOTHER. THIS ONE REFERS TO" 00460PRINT"NUMBERS FOUND IN A TABLE OF LOGARITHMS. LOOK OVER THE FOLLOWING:" 00470PRINT 00480PRINT" (1) TAN (2) TRA (3) ADV (4) ABS" 00490PRINT 00500PRINT" (5) COS (6) PAC (7) MON (8) SIN" 00510PRINT 00520PRINT"FOUR OF THEM ARE STANDARD FUNCTIONS; FOUR ARE NOT. CAN YOU PICK" 00530PRINT"ONE OUT THAT IS? TYPE IN ITS NUMBER ONLY. WHAT WOULD YOU SAY"; 00540INPUTA 00550PRINT 00560IFA=1THEN620 00570IFA=4THEN620 00580IFA=5THEN620 00590IFA=8THEN620 00600PRINT"YOU DIDN'T PICK ONE OF THEM THAT TIME. TRY ONCE MORE. WHICH"; 00610GOTO540 00620PRINT"THIS IS ONE OF THEM. THREE ARE TRIGONOMETRIC FUNCTIONS: 'TAN'" 00630PRINT"MEANS 'TANGENT', 'SIN' MEANS 'SINE', AND 'COS' MEANS 'COSINE'." 00640PRINT"ONE ('ABS') MEANS TO USE THE POSITIVE VALUE FOR WHATEVER IS" 00650PRINT"BEING CONSIDERED. THIS IS THE 'ABSOLUTE VALUE' - OFTEN REQUIRED." 00660PRINT 00670PRINT"EACH FUNCTION IS FOLLOWED BY AN EXPRESSION IN PARENTHESES, KNOWN" 00680PRINT"AS THE 'ARGUMENT'; IT IS WHAT THE FUNCTION OPERATES ON. EXAMPLE:" 00690PRINT"'ABS(Y)' MEANS 'Y' IS TO BE MADE POSITIVE REGARDLESS OF SIGN, OR" 00700PRINT"ITS 'ABSOLUTE VALUE' IS TO BE USED. HERE 'Y' IS THE ARGUMENT." 00710PRINT 720PRINT"WE HAVE MENTIONED 4 STANDARD FUNCTIONS, BASIC HAS OTHERS" 730PRINT"AVAILABLE TO THE USER, AMONG WHICH ARE:" 00740PRINT 750PRINT" (1) ATN(U) (2) EXP(U) (3) INT(U) (4) RND(U)" 760PRINT" (5) FIX(U) (6) LOG10(U) (7) SGN(U) (8) RND (9) PI" 765 PRINT 00770PRINT"HERE THE 'U' SIMPLY REPRESENTS THE ARGUMENT. ONE OF THE ABOVE IS" 00780PRINT"FOR TAKING ONLY THE WHOLE NUMBER PART OF A DECIMAL NUMBER. WHICH" 00790PRINT"DO YOU THINK THIS ONE MIGHT BE (TYPE NUMBER) "; 00800INPUTW 00810PRINT 820IF W=3 OR W=5 THEN 850 830PRINT"NO, IT COULD BE 'INT' OR 'FIX'. 'INT' STANDS FOR 'INTEGER'" 840 GOTO 851 850PRINT"THAT'S RIGHT. IT COULD BE 'INT' OR 'FIX'. 'INT' STANDS FOR 'INTEGER'" 851PRINT"WHICH RETURNS THE LARGEST INTEGER IN U. 'FIX' RETURNS THE INTEGER" 852PRINT"PART OF U ONLY. FOR EXAMPLE:" 853PRINT" INT(-2.7) = -3" 854PRINT" FIX(-2.7) = -2" 855PRINT" INT(34.8) = 34" 856PRINT 860PRINT"WHICH DO YOU SUPPOSE IS USED TO GENERATE RANDOM NUMBERS"; 00870INPUTR 00880PRINT 890IF R=4 OR R=8 THEN 920 00900PRINT"YOU NEED ANOTHER GUESS. LOOK AT THE LETTER COMBINATIONS. TRY.."; 00910GOTO870 00920PRINT"GOOD. ALSO, 'ATN' MEANS 'ARCTANGENT', A TRIGONOMETRIC FUNCTION," 00930PRINT"AND 'EXP' MEANS 'EXPONENTIAL', WHICH IS THE ANTILOG FUNCTION." 00940PRINT"IF YOU USE A TRIGONOMETRIC FUNCTION, PLEASE NOTE: THEY INVOLVE" 950PRINT"RADIANS, NOT DEGREES. ALSO, THE 'LOG' FUNCTION IS BASED ON" 960PRINT"THE 'NATURAL' LOGARITHMS. 'LOG10' IS USED TO OBTAIN 'COMMON' LOGS." 965PRINT"THE 'SGN' FUNCTION RETURNS THE INTEGER 1 PRECEEDED BY THE SIGN OF" 966PRINT"THE ARGUMENT. FOR EXAMPLE:" 967PRINT\PRINT" SGN(-4.2) = -1"\PRINT" SGN(273.51) = 1"\PRINT 968PRINT"NOTE THAT 'RND' IS EQUIVALENT TO 'RND(U)'; EACH RETURNS A" 969PRINT"RANDOM NUMBER. 'PI' HAS THE CONSTANT VALUE 3.14159." 00970PRINT 00980PRINT"TYPE CHOICE NUMBER: WOULD YOU LIKE PRACTICE USING: (1) A 'TRIG'" 00990PRINT"FUNCTION? (2) A 'LOG' FUNCTION? (3) ANOTHER STANDARD FUNCTION?" 00992PRINT"OR (4) NO STANDARD FUNCTION? WHATS YOUR PREFERENCE"; 00994INPUTZ1 00996IFZ1=1THEN1010 00997IFZ1=2THEN1010 00998IFZ1=3THEN1010 00999IFZ1=4THEN1020 01000PRINT 01003PRINT"I DO NOT UNDERSTAND YOUR CHOICE. PLEASE RETYPE."; 01004GOTO994 01010PRINT 1014PRINT"GOOD. CALL 'TUTR11' AND PROCEED." 1015 GOTO 1150 1020 PRINT"GOOD, CALL 'TUTR12' AND PROCEED." 1025 GOTO 1150 1130PRINT"THAT'S FINE. WE'LL USE THE PROGRAM 'TUTR10' FOR THIS" 1132PRINT"PURPOSE. TYPE 'RUN TUTR10' AND I WILL PROVIDE STEP-BY-STEP" 1134PRINT"DIRECTIONS ON HOW TO PROCEED. AFTER YOU HAVE HAD A CHANCE TO" 1136PRINT"TRY IT, WE CAN DISCUSS THE RESULTS IN THIS PROGRAM WHEN YOU" 1137PRINT"CALL IT BACK (AFTER RUNNING 'TUTR10'). I'LL BE WAITING FOR" 1138PRINT"YOU!!" 1150 END