1  REM  ****  HP BASIC PROGRAM LIBRARY  *******************************
2  REM
3  REM        INTGR:   COMPUTES A DEFINITE INTEGRAL BY MEANS OF THE
4  REM                  THREE POINT GAUSSIAN INTEGRATION FORMULA
5  REM        36698 REV  A   10/73
6  REM
7  REM  ****  CONTRIBUTED PROGRAM  ************************************
9000  REM INTGR---THREE POINT GAUSSIAN INTEGRATION ROUTINE
9001  READ Q[1],Q[2],Q[3]
9002  READ W[1],W[2],W[3]
9003  DATA -.774597,0,.774597
9004  DATA .555556,.888889,.555556
9005  READ Q1,Q2,Q3
9006  PRINT "THE INTEGRAL FROM"Q1"TO"Q2"FOR"Q3"INTERVALS IS";
9007  LET Z1=0
9008  LET Z2=(Q2-Q1)/Q3
9009  LET Z3=Z2/2
9010  FOR I=1 TO Q3
9011  LET Z4=Q1+I*Z2-Z3
9012  LET Z5=0
9013  FOR J=1 TO 3
9014  LET Q=Q[J]*Z3+Z4
9015  GOSUB 9100
9016  LET Z5=Z5+W[J]*Z
9017  NEXT J
9018  LET Z1=Z1+Z5
9019  NEXT I
9020  LET Z1=Z1*Z3
9021  PRINT Z1"."
9022  STOP 
9100  LET Z=EXP(Q)
9101  RETURN 
9200  DATA 0,1,10
9999  END 
