SUB EDIT00(NR,NC,IFLG)
         ON ERROR GOTO <<ERA>>
         IFLG=0 \ &
         DIM #3,B(250,15)
         H9=.9E-38
         MAXR=250
         MAXC=15
<<*TYH>> PRINT \ PRINT "TYPE 'HELP' FOR A LIST OF EDIT CODES"
<<*TYP>> INPUT "TYPE EDIT CODE (0 FOR NO MORE EDIT)";A$
         PRINT
         IF A$<>"HELP" GOTO <<SE1>>
         PRINT \ PRINT "THE FOLLOWING CODES SIGNIFY THE EDIT OPTIONS"
         PRINT "     1 - PRINT ENTIRE MATRIX"         \ &
         PRINT "     2 - PRINT SUBMATRIX"             \ &
         PRINT "     3 - DELETE A COLUMN"             \ &
         PRINT "     4 - ADD A COLUMN"                \ &
         PRINT "     5 - DELETE A ROW"                \ &
         PRINT "     6 - ADD A ROW"                   \ &
         PRINT "     7 - REPLACE AN ENTIRE ROW"       \ &
         PRINT "     8 - REPLACE AN INDIVIDUAL VALUE" \ &
         PRINT "     0 - NO MORE EDIT"                \ &
         GOTO <<TYP>>
<<*SE1>> ON ERROR GOTO <<ERC>>
         N=VAL(A$)
         IF N>=0  AND N<=8  GOTO <<ON2>>
         PRINT "EDIT CODE MUST BE BETWEEN 0 AND 8. PLEASE TRY AGAIN" \ &
         GOTO <<TYH>>
<<*ERC>> PRINT "INVALID EDIT CODE.  PLEASE TRY AGAIN" \ &
         RESUME <<TYH>>
<<*ON2>> ON ERROR GOTO <<ERB>>
         IF N=0 GOTO <<ENE>>
<<*ONN>> ON N GOTO <<E>>,<<F>>,<<H>>,<<I>>,<<D>>,<<C>>,<<B>>,<<A>>
              !     REPLACE AN INDIVIDUAL VALUE
<<*A>>   INPUT "TYPE ROW AND COLUMN OF VALUE TO BE REPLACED";NR1;NC1
         IF NR1>=1 AND NR1<=NR AND NC1>=1 AND NC1<=NC THEN GOTO <<A1>>
         PRINT "THE ROW NUMBER MUST BE BETWEEN 1 AND";NR \ &
         PRINT "THE COLUMN NUMBER MUST BE BETWEEN 1 AND";NC \ &
         PRINT "PLEASE TRY AGAIN" \ &
         GOTO <<A>>
<<*A1>>  INPUT "NEW VALUE: (X FOR MISSING)";L$
         IF L$<>"X" GOTO <<A2>>
         IF B(NR1,NC1)=H9 THEN GOTO <<TYP>> ELSE &
           B(NR1,NC1)=H9  \ B(0,NC1)=B(0,NC1)-1. \ GO TO <<A3>>
<<*A2>>  A=VAL(L$)
         IF B(NR1,NC1)=H9 THEN B(0,NC1)=B(0,NC1)+1.
         B(NR1,NC1)=A
<<*A3>>  IFLG=1
         PRINT
         GOTO <<TYP>>
              !     REPLACE AN ENTIRE ROW
<<*B>>   INPUT "WHICH ROW DO YOU WANT TO REPLACE";NR1
         IF NR1>=1 AND NR1<=NR GOTO <<C1>>
         PRINT "THE ROW NUMBER MUST BE BETWEEN 1 AND";NR \ &
         PRINT "PLEASE TRY AGAIN" \ &
         GOTO <<B>>
              !     ADD A ROW
<<*C>>   IF NR=MAXR   THEN PRINT "YOU CANNOT ADD A ROW.  YOUR DATA" \ &
         PRINT "ALREADY CONTAINS";MAXR;" ROWS" \ &
         GOTO <<TYP>>
         NR=NR+1
         NR1=NR
         PRINT "NUMBER OF NEW ROW IS";NR
<<*C1>>  PRINT "TYPE";NC;" NUMBERS, ANY AMOUNT PER LINE" \ &
         PRINT "SEPARATE NUMBERS WITH A COMMA "; &
               "BUT DO NOT END A LINE WITH A COMMA" \ &
         PRINT "IF A VALUE IS MISSING, TYPE AN X WHERE THE VALUE"; &
               " WOULD NORMALLY OCCUR"
         IFLG=1
         INPUT LINE L$
         L$=LEFT(L$,LEN(L$)-2)+","
         FOR K=1 TO NC
<<*C2>>    IZ=INSTR(1,L$,",")
           IF IZ>0 THEN GOTO <<C4>>
<<*C3>>      PRINT "TYPE IN MORE VALUES"
             INPUT LINE L$
             L$=LEFT(L$,LEN(L$)-2)+","
             GO TO <<C2>>
<<*C4>>    A$=LEFT(L$,IZ-1) \ &
           IF A$="X" THEN Y=H9 ELSE Y=VAL(A$)
           IF N=3 GOTO <<C5>>
           IF B(NR1,K)=H9 AND Y<>H9 THEN B(0,K)=B(0,K)+1.
           IF B(NR1,K)<>H9 AND Y=H9 THEN B(0,K)=B(0,K)-1.
           GO TO <<C6>>
<<*C5>>    IF Y<>H9 THEN B(0,K)=B(0,K)+1.
<<*C6>>    B(NR1,K)=Y
         L$=RIGHT(L$,IZ+1)
         NEXT K
         PRINT "THE DATA HAS BEEN ADDED TO YOUR MATRIX IN ROW";NR1 \ &
         GOTO <<TYP>>
              !     DELETE A ROW
<<*D>>   IF NR>1 GO TO <<D1>>
         PRINT "YOU CANNOT DELETE A ROW. . ." \ &
         PRINT "YOU HAVE ONLY ONE ROW LEFT" \ &
         GOTO <<TYP>>
<<*D1>>  INPUT "WHAT ROW NUMBER IS TO BE DELETED";ND
         IF ND>=1 AND ND<=NR GOTO <<D2>>
         PRINT "THE ROW NUMBER MUST BE BETWEEN 1 AND";NR \ &
         PRINT "PLEASE TRY AGAIN" \ &
         GOTO <<D1>>
<<*D2>>  FOR J=1 TO NC
           IF B(ND,J)<>H9 THEN B(0,J)=B(0,J)-1.
         NEXT J
         IF ND=NR THEN NR=NR-1 \ GO TO <<D3>>
         FOR I=ND+1 TO NR
           B(I-1,J)=B(I,J) FOR J=1 TO NC
         NEXT I
         NR=NR-1
<<*D3>>  PRINT "THE NEW MATRIX HAS";NR;" ROWS AND";NC;" COLUMNS"
         IFLG=1
         GOTO <<TYP>>
              !     PRINT ENTIRE MATRIX
<<*E>>   NC1,NC8,NR1=1 \ NC2,NC9=NC \ NR2=NR
         GOTO <<F4>>
              !     PRINT SUBMATRIX
<<*F>>   IS=1
         ON ERROR GOTO <<FE>>
<<*F1>>  INPUT "TYPE FIRST ROW, LAST ROW TO PRINT";NR1,NR2
         IF NR1>=1 AND NR1<=NR AND NR2>=NR1 AND NR2<=NR GOTO <<F2>>
         PRINT "ROW NUMBERS MUST BE BETWEEN 1 AND";NR \ &
         PRINT "PLEASE TRY AGAIN " \ &
         GO TO <<F1>>
<<*F2>>  IS=2
         INPUT "TYPE FIRST COLUMN, LAST COLUMN TO PRINT";NC1,NC2
         IF NC1>=1 AND NC1<=NC AND NC2>=NC1 AND NC2<=NC GOTO <<F3>>
         PRINT "COLUMN NUMBERS MUST BE BETWEEN 1 AND";NC \ &
         PRINT "PLEASE TRY AGAIN" \ &
         GOTO <<F2>>
<<*F3>>  NC8=NC1 \ &
         NC9=NC2
<<*F4>>  IF (NC9-NC8)>5 THEN NC9=NC8+5
         PRINT \ PRINT "ROW";TAB(35);"COLUMN" \ PRINT
         I=10
         FOR K=NC8 TO NC9
           PRINT TAB(I);K;
           I=I+11
         NEXT K
         PRINT
         FOR I=NR1 TO NR2
            PRINT USING "###  ",I;
            FOR J=NC8 TO NC9
              IF B(I,J)=H9 THEN PRINT SPACE$(11); ELSE &
              PRINT USING " #####.####",B(I,J);
            NEXT J
            PRINT
         NEXT I
         PRINT \ PRINT
         IF NC9<NC2 THEN NC8=NC9+1 \ NC9=NC2 \ GOTO <<F4>>
         GOTO <<TYP>>
<<*FE>>  PRINT "YOU TYPED NON-NUMERIC ROW OR COLUMN NUMBERS" \ &
         PRINT "PLEASE RETYPE NUMBERS SEPARATED BY A COMMA"
         IF IS=1 THEN RESUME <<F1>> ELSE RESUME <<F2>>
              !     DELETE A COLUMN
<<*H>>   IF NC>1 GO TO <<H1>>
         PRINT "YOU CANNOT DELETE A COLUMN. . ." \ &
         PRINT "YOU HAVE ONLY ONE COLUMN LEFT" \ &
         GOTO <<TYP>>
<<*H1>>  INPUT "WHAT COLUMN IS TO BE DELETED";ND
         IF ND>=1 AND ND<=NC GOTO <<H2>>
         PRINT "THE COLUMN NUMBER MUST BE BETWEEN 1 AND";NC  \ &
         PRINT "PLEASE TRY AGAIN" \ &
         GOTO <<H1>>
<<*H2>>  IF ND=NC THEN NC=NC-1 \ GOTO<<D3>>
         FOR K=0 TO NR
           B(K,J)=B(K,J+1) FOR J=ND TO NC-1
         NEXT K
         NC=NC-1
         GO TO <<D3>>
              !     ADD A COLUMN
<<*I>>   IF NC=MAXC THEN PRINT "YOU CANNOT ADD A COLUMN.  YOUR DATA" \ &
           PRINT "ALREADY CONTAINS";MAXC;" COLUMNS" \ &
           GOTO <<TYP>>
         NC=NC+1
         PRINT "NUMBER OF NEW COLUMN IS";NC
         PRINT "TYPE";NR;" NUMBERS, ANY AMOUNT PER LINE" \ &
         PRINT "SEPARATE NUMBERS WITH A COMMA, BUT DO NOT END A LINE"; &
               " WITH A COMMA" \ &
         PRINT "IF A VALUE IS MISSING, TYPE AN X WHERE THE VALUE"; &
               " WOULD NORMALLY OCCUR"
         IFLG=1
         INPUT LINE L$
         L$=LEFT(L$,LEN(L$)-2)+","
         B(0,NC)=0.
         FOR K=1 TO NR
<<*I1>>    IZ=INSTR(1,L$,",")
           IF IZ>0 GOTO <<I3>>
<<*I2>>      PRINT "TYPE IN MORE VALUES"
             INPUT LINE L$
             L$=LEFT(L$,LEN(L$)-2)+","
             GOTO <<I1>>
<<*I3>>    A$=LEFT(L$,IZ-1) \ IF A$="X" THEN B(K,NC)=H9 ELSE &
           B(K,NC)=VAL(A$) \ B(0,NC)=B(0,NC)+1.
         L$=RIGHT(L$,IZ+1)
         NEXT K
         PRINT "THE DATA HAS BEEN ADDED TO YOUR MATRIX IN COLUMN";NC
         GOTO <<TYP>>
<<*ERA>> RESUME <<TYP>>
<<*ERB>> PRINT "PLEASE TYPE ONLY NUMBERS WHEN NUMBERS ARE ASKED FOR" \ &
         PRINT "WHEN TWO OR MORE NUMBERS ARE REQUESTED, SEPARATE"; &
               " THEM WITH COMMAS" \ &
         PRINT "BUT DO NOT END A LINE WITH A COMMA"
         IF ERL=<<A>> THEN RESUME <<A>>
         IF ERL=<<A2>> THEN RESUME <<A1>>
         IF ERL=<<B>> THEN RESUME <<B>>
         IF ERL=<<D1>> THEN RESUME <<D1>>
         IF ERL=<<H1>> THEN RESUME <<H1>>
         IF N=4 OR N=6 OR N=7 THEN &
           PRINT "THE FIRST";K-1;" VALUES HAVE BEEN PUT INTO YOUR"; &
                 " MATRIX"
         IF N=6 OR N=7 THEN RESUME <<C3>> ELSE IF N=4 THEN &
           RESUME <<I2>> ELSE RESUME <<ONN>>
<<*ENE>> SUBEND