10  COM S[300],B[300],C[300],R[300],F[300],G[300]
20  COM T[25],G0,G1,G2,G3,G4,G5,G6,G7,G8,G9
30  COM H[100],I[100],M0,M1,A0
40  COM J[20],K[20],M[20],N[20]
50  COM R$[7],R9
60  COM S1
70  COM H2,H3,H4,H5,H6,H7,H8,H9,P1
80  COM J1,J2,J3,J4,J5,J6,J7,J8
100  COM C$[4],Z[4],E$[4],Y[4]
110  COM Q$[7],Q9
120  COM N0,N1
130  COM I9,I0
140  COM I2
150  COM P[9],Q[9],O[9],U[9]
160  COM D[200,10]
170  COM A[9,9],E[9]
180  COM F1,F2,F3,S2,T1,I1
190  COM I
200  COM S6
310  MAT D=ZER
320  MAT P=ZER
330  MAT A=ZER[P1,P1]
340  LET F1=F3=F4=1
350  F2=10
400  Q$="$IDA53D"
410  Q9=430
420  CHAIN "$IDA53A"
430  PRINT LIN(1),"INITIAL-SUM-OF SQUARES =",S1
440  PRINT LIN(1),"ITERATION NUMBER  ";F1
450  LET F3=F3/F2
460  I1=0
470  REM
480  REM  CALCULATE NUMERICAL DERIVATIVES FOR STEEPEST DESCENT
490  REM
500  I=1
510  LET T1=T[I]
520  P[I]=.01*T[I]
530  T[I]=T[I]+P[I]
540  Q[I]=0
600  FOR J=I2 TO G0
610  LET D[J,10]=R[J]
620  NEXT J
625  Q$="$IDA53D"
630  LET Q9=650
640  CHAIN "$IDA53A"
650  IF P1 <= 9 THEN 660
652  PRINT "YOU CANNOT ESTIMATE MORE THAN 9 PARAMETERS, TRY AGAIN"
654  GOTO 790
660  FOR J=I2 TO G0
670  LET D[J,I]=R[J]
680  R[J]=D[J,10]
690  NEXT J
700  FOR J=I2 TO G0
710  LET D[J,I]=R[J]-D[J,I]
720  Q[I]=Q[I]+D[J,I]*R[J]
730  NEXT J
740  LET Q[I]=Q[I]/P[I]
750  T[I]=T1
760  I=I+1
770  IF (I <= P1) THEN 510
780  CHAIN "$IDA53E"
790  END 
