500 REM ****INTGRT****MATHEMATICS PROGRAM****
510 REM ***VERSION 1****7/31/69*****
520 REM COMPUTER NUMERIC INTEGRAL OF A FUNCTION
530 REM REVISED APRIL, 1972  ANDY ROTH C.C.G.
1000 INPUT "HAVE YOU DEFINED YOUR FUNCTION";D$
1003 IF D$="YES" THEN 1080
1005 PRINT" PLEASE ENTER YOUR FUNCTION IN THE FOLLWING MANNER:"
1008 PRINT "AFTER THE FIRST 'READY"'"
1011 PRINT"PLEASE TYPE '1079 DEF FNF(X)=<YOUR FUNCTION>'"
1014 PRINT" YOUR FUNCTION SHOULD BE LIKE 'SIN (X) OR X^2'"
1015 PRINT "HIT 'RETURN' AND THEN TYPE 'RUNNH'"
1016 GO TO 1400
1079 DEF FNF(X)=SIN(X)
1080 INPUT "WHAT IS THE LOWER X BOUNDRY";A
1083 INPUT "WHAT IS THE UPPER X BOUNDRY";B
1085 INPUT"WHAT IS THE ACCEPTABLE ERROR";E
1100  H=B-A
1120  T=(FNF(A)+FNF(B))*H
1140  M=0
1160  T=(T+M)/2
1180  M=0
1200 FOR X=A+H/2 TO B STEP H
1220  M=M+FNF(X)
1240 NEXT X
1260  M=M*H
1280  S=(T+2*M)/3
1300  H=H/2
1320 IF ABS(T-M)/ABS(S)>E THEN 1160
1340 PRINT "INTEGRAL = "S
1400 END