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Treebeard's String-Math
#21
(07-30-2022, 01:05 AM)Jack Wrote: Pete, I looked at your demo and I couldn't figure out how I would use your math engine to perform any math problem, it's horrifically complex
suppose that I wanted to code a simple factorial
Code: (Select All)
input "n ";n
f=1
for i=1 to n
    f=f*i
next
print f
show me how simple it is with your math-engine
I am signing off for the weekend, see you Sunday

Well it ain't made to be easy. It was made to be a calculator, but I just got rid of the extra stuff and used the sub, so here you go...

Code: (Select All)
_SCREENMOVE 0, 0
WIDTH 170, 25
start:
operator$ = "*"
' snconvert% = -1
INPUT "n "; n
f = 1
stringmatha$ = LTRIM$(STR$(f))
FOR i = 1 TO n
    stringmathb$ = LTRIM$(STR$(i))
    CALL stringmath(stringmatha$, operator$, stringmathb$, runningtotal$, snconvert%, round_total%, show_rounding%, comma_display%, currency_display%, limit&&)
    stringmatha$ = runningtotal$
NEXT

PRINT "String Total:  "; runningtotal$
PRINT: CLEAR: GOTO start

SUB stringmath (stringmatha$, operator$, stringmathb$, runningtotal$, snconvert%, round_total%, show_rounding%, comma_display%, currency_display%, limit&&)
    stringmathround$ = ""
    IF limit&& > 2147483640 THEN limit&& = 2147483640
    IF limit&& = 0 THEN limit&& = 1700 ' Default.

    IF RIGHT$(UCASE$(runningtotal$), 1) = "R" THEN runningtotal$ = MID$(runningtotal$, 1, LEN(runningtotal$) - 1) 'Strip off rounding designation.
    ' Check running total. If S.N. convert to numeric for operations.
    IF INSTR(runningtotal$, ",") <> 0 OR INSTR(runningtotal$, "e") <> 0 THEN
        holdstringmathb$ = stringmathb$
        stringmathb$ = runningtotal$
        IF INSTR(runningtotal$, ",") <> 0 THEN GOSUB comma_removal ELSE GOSUB scientific_to_numeric
        runningtotal$ = stringmathb$: stringmathb$ = holdstringmathb$: holdstringmathb$ = ""
    END IF
    ' Check input number. If S.N. convert to numeric for operations.
    IF INSTR(UCASE$(stringmathb$), "D") <> 0 OR INSTR(UCASE$(stringmathb$), "E") <> 0 THEN
        '''GOSUB validate_string_number
        IF stringmathb$ = "invalid number" THEN EXIT SUB
        GOSUB scientific_to_numeric
    END IF

    IF runningtotal$ = "" THEN
        '''GOSUB validate_string_number
        IF stringmathb$ = "invalid number" THEN EXIT SUB

        IF LEFT$(stringmathb$, 1) = "-" THEN
            stringmathb$ = MID$(stringmathb$, 2)
            n2sign$ = "-"
        ELSE
            n2sign$ = ""
        END IF
        GOSUB limit_round_convert
        IF stringmathb$ = "overflow" THEN
            n2sign$ = "": PRINT "Validated: "; stringmathb$: EXIT SUB
        END IF
        runningtotal$ = n2sign$ + stringmathb$: n2sign$ = ""
        IF stringmathround$ <> "" THEN runningtotal$ = runningtotal$ + stringmathround$
        '''PRINT "Validated: "; runningtotal$
        IF INSTR(LCASE$(stringmathb$), "e") <> 0 THEN BEEP: GOSUB scientific_to_numeric
    ELSE
        ''' GOSUB validate_string_number
        '''PRINT "Validated: "; stringmathb$
        IF stringmathb$ = "invalid number" THEN EXIT SUB
        IF INSTR(UCASE$(stringmathb$), "e") <> 0 THEN GOSUB scientific_to_numeric
    END IF
    IF runningtotal$ <> "" THEN stringmatha$ = runningtotal$

    SELECT CASE operator$
        CASE "+", "-"
            string_add_subtract:
            IF INSTR(stringmatha$, ".") <> 0 THEN ' Evaluate sum for decimal fraction.
                sumplace& = LEN(stringmatha$) - INSTR(stringmatha$, ".")
                stringmatha$ = MID$(stringmatha$, 1, INSTR(stringmatha$, ".") - 1) + MID$(stringmatha$, INSTR(stringmatha$, ".") + 1) ' Strip out decimal
            END IF
            IF INSTR(stringmathb$, ".") <> 0 THEN ' Evaluate number for decimal fraction.
                numplace& = LEN(stringmathb$) - INSTR(stringmathb$, ".")
                stringmathb$ = MID$(stringmathb$, 1, INSTR(stringmathb$, ".") - 1) + MID$(stringmathb$, INSTR(stringmathb$, ".") + 1) ' Strip out decimal
            END IF
            IF sumplace& > numplace& THEN addsubplace& = sumplace& ELSE addsubplace& = numplace&
            IF sumplace& > addsubplace& THEN
                stringmatha$ = stringmatha$ + STRING$(sumplace& - addsubplace&, "0")
            ELSEIF addsubplace& > sumplace& THEN
                stringmatha$ = stringmatha$ + STRING$(addsubplace& - sumplace&, "0")
            END IF
            IF numplace& > addsubplace& THEN
                stringmathb$ = stringmathb$ + STRING$(numplace& - addsubplace&, "0")
            ELSEIF addsubplace& > numplace& THEN
                stringmathb$ = stringmathb$ + STRING$(addsubplace& - numplace&, "0")
            END IF ' END Decimal evaluations.

            IF LEFT$(stringmatha$, 1) = "-" THEN sign_input$ = "-" ELSE sign_input$ = "+"
            IF LEFT$(stringmathb$, 1) = "-" THEN sign_total$ = "-" ELSE sign_total$ = "+"

            addsubsign% = 0
            SELECT CASE sign_input$ + operator$ + sign_total$
                CASE "+++", "+--"
                    operator$ = "+"
                    IF LEFT$(stringmathb$, 1) = "-" THEN stringmathb$ = MID$(stringmathb$, 2)
                CASE "++-", "+-+"
                    operator$ = "-"
                    IF LEFT$(stringmathb$, 1) = "-" THEN stringmathb$ = MID$(stringmathb$, 2)
                    IF VAL(stringmathb$) > VAL(stringmatha$) THEN SWAP stringmatha$, stringmathb$: addsubsign% = -1
                CASE "---", "-++"
                    operator$ = "-"
                    IF LEFT$(stringmatha$, 1) = "-" THEN stringmatha$ = MID$(stringmatha$, 2)
                    IF LEFT$(stringmathb$, 1) = "-" THEN stringmathb$ = MID$(stringmathb$, 2)
                    IF VAL(stringmathb$) > VAL(stringmatha$) THEN SWAP stringmatha$, stringmathb$ ELSE addsubsign% = -1
                CASE "--+", "-+-"
                    operator$ = "+"
                    IF LEFT$(stringmatha$, 1) = "-" THEN stringmatha$ = MID$(stringmatha$, 2)
                    IF LEFT$(stringmathb$, 1) = "-" THEN stringmathb$ = MID$(stringmathb$, 2)
                    addsubsign% = -1
            END SELECT

            IF LEN(stringmatha$) > LEN(stringmathb$) THEN
                stringmathb$ = STRING$(LEN(stringmatha$) - LEN(stringmathb$), "0") + stringmathb$
            ELSEIF LEN(stringmatha$) < LEN(stringmathb$) THEN
                stringmatha$ = STRING$(LEN(stringmathb$) - LEN(stringmatha$), "0") + stringmatha$
            END IF
            addsubx1$ = ""

            SELECT CASE operator$
                CASE "+", "="
                    FOR addsubii& = LEN(stringmatha$) TO 1 STEP -1
                        addsubx1% = VAL(MID$(stringmatha$, addsubii&, 1)) + VAL(MID$(stringmathb$, addsubii&, 1)) + addsubcarry%
                        IF addsubx1% > 9 THEN addsubx1% = addsubx1% - 10: addsubcarry% = 1 ELSE addsubcarry% = 0
                        addsubx1$ = LTRIM$(STR$(addsubx1%)) + addsubx1$
                    NEXT
                    IF addsubcarry% THEN addsubx1$ = "1" + addsubx1$: addsubcarry% = 0
                    GOSUB replace_decimal
                CASE "-"
                    FOR addsubii& = LEN(stringmatha$) TO 1 STEP -1
                        addsubx1% = VAL(MID$(stringmatha$, addsubii&, 1)) - VAL(MID$(stringmathb$, addsubii&, 1)) + addsubcarry%
                        IF addsubx1% < 0 THEN addsubx1% = addsubx1% + 10: addsubcarry% = -1 ELSE addsubcarry% = 0
                        addsubx1$ = LTRIM$(STR$(addsubx1%)) + addsubx1$
                    NEXT
                    IF addsubx1$ <> "" AND addsubx1$ <> STRING$(LEN(addsubx1$), "0") THEN GOSUB replace_decimal
                    DO UNTIL LEFT$(addsubx1$, 1) <> "0" ' Remove leading zeros.
                        addsubx1$ = MID$(addsubx1$, 2)
                    LOOP
                    IF addsubx1$ = "" THEN
                        addsubx1$ = "0": addsubsign% = 0
                    ELSE
                        IF addsubcarry% THEN addsubx1$ = "-" + addsubx1$: addsubcarry% = 0
                    END IF
            END SELECT

            IF addsubsign% THEN
                IF LEFT$(addsubx1$, 1) = "-" THEN addsubx1$ = MID$(addsubx1$, 2) ELSE addsubx1$ = "-" + addsubx1$
            END IF
            stringmatha$ = addsubx1$: addsubx1$ = ""
            IF operationdivision% THEN RETURN
            stringmathb$ = stringmatha$: stringmatha$ = ""
            IF LEFT$(stringmathb$, 1) = "-" THEN
                stringmathb$ = MID$(stringmathb$, 2)
                n2sign$ = "-"
            ELSE
                n2sign$ = ""
            END IF
            GOSUB limit_round_convert
            IF stringmathb$ = "overflow" THEN n2sign$ = "": EXIT SUB
            GOSUB sm_converter
            runningtotal$ = n2sign$ + stringmathb$: n2sign$ = ""

        CASE "*"
            string_multiply:
            fac1$ = stringmatha$: fac2$ = stringmathb$ ' Make numbers whole numbers and remove any - sign.
            IF LEFT$(fac1$, 1) = "-" THEN fac1$ = MID$(fac1$, 2): m_sign% = -1
            IF LEFT$(fac2$, 1) = "-" THEN fac2$ = MID$(fac2$, 2): IF m_sign% THEN m_sign% = 0 ELSE m_sign% = -1
            IF INSTR(fac1$, ".") <> 0 THEN m_decimal_places& = LEN(fac1$) - INSTR(fac1$, "."): fac1$ = MID$(fac1$, 1, INSTR(fac1$, ".") - 1) + MID$(fac1$, INSTR(fac1$, ".") + 1)
            IF INSTR(fac2$, ".") <> 0 THEN m_decimal_places& = m_decimal_places& + LEN(fac2$) - INSTR(fac2$, "."): fac2$ = MID$(fac2$, 1, INSTR(fac2$, ".") - 1) + MID$(fac2$, INSTR(fac2$, ".") + 1)
            FOR m_i& = LEN(fac2$) TO 1 STEP -1 ' Multiply each charter top and bottom.
                m_k& = m_l&
                m_x2$ = MID$(fac2$, m_i&, 1)
                FOR m_j& = LEN(fac1$) TO 1 STEP -1
                    m_x1$ = MID$(fac1$, m_j&, 1)
                    IF m_product$ <> "" THEN
                        m_add$ = LTRIM$(STR$(VAL(m_x1$) * VAL(m_x2$))) + STRING$(m_k&, "0")
                        m_t& = 0: m_xproduct$ = "": m_carry% = 0
                        DO ' Add multiplied characters together.
                            m_x3$ = MID$(m_add$, LEN(m_add$) - m_t&, 1)
                            m_x4$ = MID$(m_product$, LEN(m_product$) - m_t&, 1)
                            IF m_x3$ = "" AND m_x4$ = "" THEN
                                IF m_carry% THEN m_xproduct$ = "1" + m_xproduct$
                                EXIT DO
                            END IF
                            m_g% = VAL(m_x3$) + VAL(m_x4$) + m_carry%
                            IF m_g% >= 10 THEN m_g% = m_g% - 10: m_carry% = 1 ELSE m_carry% = 0
                            m_xproduct$ = LTRIM$(STR$(m_g%)) + m_xproduct$
                            m_t& = m_t& + 1
                        LOOP
                        m_product$ = m_xproduct$: m_xproduct$ = ""
                    ELSE
                        m_product$ = LTRIM$(STR$(VAL(m_x1$) * VAL(m_x2$))) + STRING$(m_k&, "0") ' First loop makes variable here.
                    END IF
                    m_k& = m_k& + 1 ' Adds trailing zeros multiplication
                NEXT
                m_l& = m_l& + 1 ' Used to reset value for m_k& adding one trailing zer for each loop.
            NEXT
            fac1$ = "": fac2$ = "": m_l& = 0: m_k& = 0: m_t& = 0
            IF m_decimal_places& > LEN(m_product$) THEN m_product$ = STRING$(m_decimal_places& - LEN(m_product$), "0") + m_product$ ' Add any leading zeros to a decimal. Ex: .02 * .01 is factored as 002. It needs one leading zero before adding the decimal point, .0002.
            IF m_decimal_places& AND m_product$ <> "0" THEN ' Replace any decimal point.
                m_product$ = MID$(m_product$, 1, LEN(m_product$) - m_decimal_places&) + "." + MID$(m_product$, LEN(m_product$) - m_decimal_places& + 1)
            END IF
            DO UNTIL LEFT$(m_product$, 1) <> "0" ' Remove leading zeros.
                m_product$ = MID$(m_product$, 2)
            LOOP
            IF m_decimal_places& THEN
                DO UNTIL RIGHT$(m_product$, 1) <> "0" ' Remove trailing zeros in a decimal sum.
                    m_product$ = MID$(m_product$, 1, LEN(m_product$) - 1)
                LOOP
            END IF
            IF m_product$ = "" THEN m_product$ = "0": m_sign% = 0
            IF RIGHT$(m_product$, 1) = "." THEN m_product$ = MID$(m_product$, 1, LEN(m_product$) - 1) ' Remove decimal from the end of an integer total.
            IF operationdivision% THEN m_sign% = 0: RETURN
            stringmathb$ = m_product$: m_product$ = "": GOSUB limit_round_convert
            IF stringmathb$ = "overflow" THEN EXIT SUB
            GOSUB sm_converter
            runningtotal$ = stringmathb$: stringmathb$ = ""
            IF m_sign% THEN runningtotal$ = "-" + runningtotal$: m_sign% = 0

        CASE "/"
            operationdivision% = -1
            divbuffer& = LEN(stringmathb$) - LEN(stringmatha$)
            IF divbuffer& < 0 THEN divbuffer& = 0
            d2dividend$ = stringmatha$
            d1divisor$ = stringmathb$
            IF LEFT$(d1divisor$, 1) = "0" AND LEN(d1divisor$) = 1 THEN PRINT "Division by zero not allowed.": END
            IF LEFT$(d1divisor$, 1) = "-" THEN divsign% = -1: d1divisor$ = MID$(d1divisor$, 2)
            IF LEFT$(d2dividend$, 1) = "-" THEN
                IF divsign% THEN
                    divsign% = 0
                ELSE
                    divsign% = -1
                END IF
                d2dividend$ = MID$(d2dividend$, 2)
            END IF
            IF INSTR(d1divisor$, ".") <> 0 THEN
                DO UNTIL RIGHT$(d1divisor$, 1) <> "0"
                    d1divisor$ = MID$(d1divisor$, 1, LEN(d1divisor$) - 1) ' Strip off trailing zeros
                LOOP
                divplace& = LEN(d1divisor$) - INSTR(d1divisor$, ".")
                d1divisor$ = MID$(d1divisor$, 1, INSTR(d1divisor$, ".") - 1) + MID$(d1divisor$, INSTR(d1divisor$, ".") + 1) ' Strip off decimal point.
                DO UNTIL LEFT$(d1divisor$, 1) <> "0"
                    d1divisor$ = MID$(d1divisor$, 2) ' Strip off leading zeros for divisors smaller than .1
                LOOP
            END IF

            IF INSTR(d2dividend$, ".") <> 0 THEN
                d2dividend$ = d2dividend$ + STRING$(divplace& - LEN(d2dividend$) - INSTR(d2dividend$, "."), "0") ' Add any zeros based on the length of dividend at decimal - length of divisor at decimal. If less than zero, nothing added.
                divplace2& = INSTR(d2dividend$, ".")
                DO UNTIL RIGHT$(d2dividend$, 1) <> "0"
                    d2dividend$ = MID$(d2dividend$, 1, LEN(d2dividend$) - 1) ' Strip off trailing zeros
                LOOP
                d2dividend$ = MID$(d2dividend$, 1, INSTR(d2dividend$, ".") - 1) + MID$(d2dividend$, INSTR(d2dividend$, ".") + 1) ' Strip off decimal point.
            ELSE
                d2dividend$ = d2dividend$ + STRING$(divplace&, "0") ' Add any zeros based on the length of dividend at decimal - length of divisor at decimal. If less than zero, nothing added.
                divplace& = 0
            END IF
            DO
                DO
                    divremainder& = divremainder& + 1: divremainder$ = divremainder$ + MID$(d2dividend$, divremainder&, 1)
                    IF MID$(d2dividend$, divremainder&, 1) = "" THEN
                        IF divremainder$ = STRING$(LEN(divremainder$), "0") AND LEN(quotient$) > LEN(d2dividend$) THEN divflag% = -1: EXIT DO
                        divcarry& = divcarry& + 1
                        IF divcarry& = 1 THEN divplace3& = divremainder& - 1
                        IF divcarry& > limit&& + 1 + divbuffer& THEN
                            divflag% = -2: EXIT DO
                        END IF
                        divremainder$ = divremainder$ + "0" ' No more digits to bring down.
                    END IF
                    IF LEN(divremainder$) > LEN(d1divisor$) OR LEN(divremainder$) = LEN(d1divisor$) AND divremainder$ >= d1divisor$ THEN EXIT DO
                    quotient$ = quotient$ + "0"
                LOOP
                IF divflag% THEN divflag% = 0: EXIT DO
                FOR div_i% = 9 TO 1 STEP -1
                    stringmatha$ = LTRIM$(STR$(div_i%)): stringmathb$ = d1divisor$
                    m_product$ = "": GOSUB string_multiply
                    tempcutd$ = divremainder$ ' divremainder$ can be 00 or other leading zero values.
                    DO
                        IF LEN(tempcutd$) = 1 THEN EXIT DO
                        IF LEFT$(tempcutd$, 1) = "0" THEN
                            tempcutd$ = MID$(tempcutd$, 2)
                        ELSE
                            EXIT DO
                        END IF
                    LOOP
                    IF LEN(tempcutd$) > LEN(m_product$) OR LEN(tempcutd$) = LEN(m_product$) AND m_product$ <= tempcutd$ THEN EXIT FOR
                NEXT
                quotient$ = quotient$ + LTRIM$(STR$(div_i%))
                stringmatha$ = LTRIM$(STR$(div_i%)): stringmathb$ = d1divisor$
                m_product$ = "": GOSUB string_multiply
                operator$ = "-"
                stringmatha$ = divremainder$
                stringmathb$ = m_product$
                GOSUB string_add_subtract
                divremainder$ = stringmatha$
                operator$ = "/"
            LOOP
            IF divplace& = 0 AND divplace2& = 0 THEN divplace& = divplace3&
            IF divplace2& THEN divplace& = divplace& + divplace2& - 1
            IF quotient$ = "" THEN divplace& = 0 ' dividend is zero.
            IF divplace& OR divplace2& THEN
                quotient$ = MID$(quotient$, 1, divplace&) + "." + MID$(quotient$, divplace& + 1)
                DO UNTIL RIGHT$(quotient$, 1) <> "0"
                    quotient$ = MID$(quotient$, 1, LEN(quotient$) - 1) ' Strip off trailing zeros
                LOOP
                IF RIGHT$(quotient$, 1) = "." THEN quotient$ = MID$(quotient$, 1, LEN(quotient$) - 1) ' Strip off abandoned decimal.
            END IF
            DO UNTIL LEFT$(quotient$, 1) <> "0"
                quotient$ = MID$(quotient$, 2) ' Strip off leading zeros
            LOOP
            IF quotient$ = "" THEN quotient$ = "0": divsign% = 0
            operationdivision% = 0
            stringmathb$ = quotient$: quotient$ = "": GOSUB limit_round_convert
            IF stringmathb$ = "overflow" THEN divsign% = 0: EXIT SUB
            GOSUB sm_converter
            runningtotal$ = stringmathb$: stringmathb$ = ""
            IF divsign% THEN runningtotal$ = "-" + runningtotal$
    END SELECT
    IF stringmathround$ <> "" THEN runningtotal$ = runningtotal$ + stringmathround$
    EXIT SUB

    validate_string_number:
    vsn_negcnt& = 0: vsn_poscnt& = 0: vsn_depresent& = 0: decimalcnt& = 0: vsn_numberpresent& = 0: vsn_zerospresent& = 0
    IF LEFT$(stringmathb$, 1) = "-" THEN stringmathb$ = MID$(stringmathb$, 2): sm_sign$ = "-" ELSE sm_sign$ = ""
    IF LEFT$(stringmathb$, 1) = "+" THEN IF sm_sign$ <> "-" THEN stringmathb$ = MID$(stringmathb$, 2) ELSE stringmathb$ = "invalid number": RETURN
    IF INSTR(UCASE$(stringmathb$), "D") OR INSTR(UCASE$(stringmathb$), "E") THEN ' Evaluate for Scientific Notation.
        FOR sm_i& = 1 TO LEN(stringmathb$)
            validatenum$ = MID$(UCASE$(stringmathb$), sm_i&, 1)
            SELECT CASE validatenum$
                CASE "+"
                    IF vsn_depresent& THEN vsn_poscnt& = vsn_poscnt& + 1 ELSE stringmathb$ = "invalid number": RETURN
                CASE "-"
                    IF vsn_depresent& THEN vsn_negcnt& = vsn_negcnt& + 1 ELSE stringmathb$ = "invalid number": RETURN
                CASE "0" TO "9"
                    vsn_numberpresent& = -1
                CASE "D", "E"
                    vsn_depresent& = vsn_depresent& + 1
                    IF decimalcnt& = 0 AND sm_i& <> 2 OR vsn_depresent& > 1 OR vsn_numberpresent& = 0 OR vsn_negcnt& > 1 OR vsn_poscnt& > 1 OR vsn_negcnt& = 1 AND vsn_poscnt& >= 1 THEN vsn_numberpresent& = 0: EXIT FOR
                    vsn_numberpresent& = 0
                    MID$(stringmathb$, sm_i&, 1) = "e" ' Standardize
                CASE "."
                    decimalcnt& = decimalcnt& + 1
                    IF sm_i& <> 2 THEN vsn_numberpresent& = 0: EXIT FOR
                CASE ELSE
                    vsn_numberpresent& = 0: EXIT FOR
            END SELECT
        NEXT
        IF decimalcnt& = 0 THEN stringmathb$ = MID$(stringmathb$, 1, 1) + "." + MID$(stringmathb$, 2) ' Standardize "."
        IF vsn_numberpresent& = 0 OR vsn_negcnt& = 1 AND vsn_poscnt& = 1 OR decimalcnt& > 1 OR INSTR(stringmathb$, ".") <> 2 THEN stringmathb$ = "invalid number": RETURN
        vsn_depresent& = INSTR(stringmathb$, "e")
        sm_x$ = MID$(stringmathb$, vsn_depresent& + 1, 1) ' Standardize exponent "+" these two lines.
        IF sm_x$ <> "+" AND sm_x$ <> "-" THEN stringmathb$ = MID$(stringmathb$, 1, vsn_depresent&) + "+" + MID$(stringmathb$, vsn_depresent& + 1)
        IF MID$(stringmathb$, vsn_depresent& + 2, 1) = "0" THEN
            IF MID$(stringmathb$, vsn_depresent& + 3, 1) <> "" THEN stringmathb$ = "invalid number": RETURN ' No leading zeros allowed in exponent notation.
        END IF
        jjed& = INSTR(stringmathb$, "e") ' Get position of notation.
        valexpside$ = MID$(stringmathb$, jjed&) ' These two lines break up into number and notation
        stringmathb$ = MID$(stringmathb$, 1, jjed& - 1) ' stringmathb$ is +- single digit whole number, decimal point and decimal number. valexpside$ is notation, sign and exponent.
        DO UNTIL RIGHT$(stringmathb$, 1) <> "0" ' Remove any trailing zeros for number. Example 1.0d3 or 1.0000d3, etc.
            stringmathb$ = MID$(stringmathb$, 1, LEN(stringmathb$) - 1)
        LOOP
        IF VAL(MID$(stringmathb$, 1, INSTR(stringmathb$, ".") - 1)) = 0 THEN
            IF RIGHT$(stringmathb$, 1) = "." THEN
                stringmathb$ = "0.e+0" ' Handles all types of zero entries.
            ELSE
                stringmathb$ = "invalid number": RETURN
            END IF
            RETURN
        END IF
        stringmathb$ = sm_sign$ + stringmathb$ + valexpside$
        RETURN
    ELSE
        FOR sm_i& = 1 TO LEN(stringmathb$)
            validatenum$ = MID$(stringmathb$, sm_i&, 1)
            SELECT CASE validatenum$
                CASE "."
                    decimalcnt& = decimalcnt& + 1
                CASE "0"
                    vsn_zerospresent& = -1
                CASE "1" TO "9"
                    vsn_numberpresent& = -1
                CASE "$"
                CASE ELSE
                    stringmathb$ = "invalid number": RETURN
            END SELECT
        NEXT
        IF decimalcnt& > 1 OR vsn_negcnt& > 1 OR vsn_poscnt& > 1 OR vsn_negcnt& >= 1 AND vsn_poscnt& >= 1 THEN
            stringmathb$ = "invalid number": RETURN
        END IF
        IF INSTR(stringmathb$, "$") THEN GOSUB currency_validate
        IF INSTR(stringmathb$, ",") THEN
            GOSUB comma_validation
            IF stringmathb$ = "invalid number" THEN RETURN
            GOSUB comma_removal
        END IF
        IF RIGHT$(stringmathb$, 1) = "." THEN stringmathb$ = MID$(stringmathb$, 1, LEN(stringmathb$) - 1)
        DO UNTIL LEFT$(stringmathb$, 1) <> "0" ' Strip off any leading zeros.
            stringmathb$ = MID$(stringmathb$, 2)
        LOOP
        stringmathb$ = sm_sign$ + stringmathb$
        IF INSTR(stringmathb$, ".") THEN
            DO UNTIL RIGHT$(stringmathb$, 1) <> "0" ' Strip off any trailing zeros in a decimal.
                stringmathb$ = MID$(stringmathb$, 1, LEN(stringmathb$) - 1)
            LOOP
        END IF
        IF RIGHT$(stringmathb$, 1) = "." THEN stringmathb$ = MID$(stringmathb$, 1, LEN(stringmathb$) - 1)
        IF vsn_numberpresent& = 0 THEN
            IF vsn_zerospresent& THEN
                stringmathb$ = "0"
            ELSE
                stringmathb$ = "invalid number"
            END IF
        END IF
    END IF
    RETURN

    ' Convert to commas, currency, S.N., etc.
    sm_converter:
    IF comma_display% THEN GOSUB comma_placement
    IF currency_display% THEN GOSUB currency_convert
    IF snconvert% THEN GOSUB numeric_to_scientific
    RETURN

    ' Add in commas.
    comma_placement:
    GOSUB comma_prep
    sm_i& = 0: sm_j& = 0: sm_seed& = 0
    sm_seed& = LEN(temp_stringmathb1$) MOD 3: IF sm_seed& = 0 THEN sm_seed& = 3
    sm_m1& = LEN(temp_stringmathb1$)
    sm_m2& = (LEN(temp_stringmathb1$) - 1) \ 3
    sm_replace$ = SPACE$(sm_m1& + sm_m2&)
    DO WHILE sm_i& < sm_m1&
        MID$(sm_replace$, sm_j& + 1, sm_seed& + 1) = MID$(temp_stringmathb1$, sm_i& + 1, sm_seed&) + ","
        sm_i& = sm_i& + sm_seed&: sm_j& = sm_j& + sm_seed& + 1: sm_seed& = 3
    LOOP
    sm_replace$ = RTRIM$(sm_replace$)
    IF RIGHT$(sm_replace$, 1) = "," THEN
        stringmathb$ = MID$(sm_replace$, 1, LEN(sm_replace$) - 1)
    ELSE
        stringmathb$ = sm_replace$
    END IF
    sm_replace$ = "": temp_stringmathb1$ = ""
    RETURN

    ' Validate comma entry.
    comma_validation:
    GOSUB comma_prep
    IF INSTR(temp_stringmathb2$, ",") <> 0 OR temp_stringmathb1$ = STRING$(LEN(temp_stringmathb1$), ",") THEN
        stringmathb$ = "invalid number" ' Decimal part has comma or entry is all commas.
    ELSE
        FOR sm_i& = LEN(temp_stringmathb1$) TO 1 STEP -1
            sm_j% = sm_j% + 1
            IF sm_j% = 4 THEN
                IF MID$(temp_stringmathb1$, sm_i&, 1) <> "," THEN stringmathb$ = "invalid number": EXIT FOR
                sm_j% = 0
            END IF
        NEXT
        IF stringmathb$ <> "invalid number" THEN
            stringmathb$ = sm_sign$ + temp_stringmathb1$ + temp_stringmathb2$
        END IF
    END IF
    temp_stringmathb1$ = "": temp_stringmathb2$ = "": sm_i& = 0: sm_j% = 0: sm_sign$ = "": sm_dollar$ = ""
    RETURN

    comma_removal:
    sm_i& = 0: sm_j& = 0: sm_seed& = 0
    sm_replace$ = SPACE$(LEN(stringmathb$))
    DO
        sm_i& = INSTR(sm_seed& + 1, stringmathb$, ",")
        IF sm_i& = 0 THEN EXIT DO
        MID$(sm_replace$, sm_j& + 1, sm_i& - sm_seed& + 1) = MID$(stringmathb$, sm_seed& + 1, sm_i& - sm_seed& - 1)
        sm_j& = sm_j& + sm_i& - sm_seed& - 1
        sm_seed& = sm_i&
    LOOP
    stringmathb$ = RTRIM$(sm_replace$) + MID$(stringmathb$, sm_seed& + 1): sm_replace$ = ""
    RETURN

    comma_prep:
    IF LEFT$(stringmathb$, 1) = "-" THEN stringmathb$ = MID$(stringmathb$, 2): sm_sign$ = "-"
    temp_stringmathb1$ = stringmathb$: stringmathb$ = ""
    IF INSTR(temp_stringmathb1$, ".") THEN
        temp_stringmathb2$ = MID$(temp_stringmathb1$, INSTR(temp_stringmathb1$, ".")) ' Decimal part
        temp_stringmathb1$ = MID$(temp_stringmathb1$, 1, INSTR(temp_stringmathb1$, ".") - 1) ' Non-decimal part
    END IF
    IF LEFT$(temp_stringmathb1$, 1) = "$" THEN temp_stringmathb1$ = MID$(temp_stringmathb1$, 2): sm_dollar$ = "$"
    RETURN

    currency_validate:
    IF LEFT$(stringmathb$, 2) = "$-" OR LEFT$(stringmathb$, 2) = "$+" THEN stringmathb$ = "invalid number": RETURN
    IF LEFT$(stringmathb$, 1) = "$" THEN stringmathb$ = MID$(stringmathb$, 2)
    IF INSTR(stringmathb$, "$") THEN stringmathb$ = "invalid number": RETURN
    sm_dollar$ = "$"
    RETURN

    currency_convert:
    IF INSTR(UCASE$(stringmathb$), "D") <> 0 OR INSTR(UCASE$(stringmathb$), "E") <> 0 THEN GOSUB scientific_to_numeric
    IF INSTR(stringmathb$, ",") = 0 THEN GOSUB comma_placement
    IF INSTR(stringmathb$, ".") = 0 THEN stringmathb$ = stringmathb$ + ".00"
    IF RIGHT$(stringmathb$, 1) = "." THEN stringmathb$ = stringmathb$ + "00"
    IF MID$(stringmathb$, LEN(stringmathb$) - 2, 1) <> "." THEN stringmathb$ = stringmathb$ + "0"
    IF MID$(stringmathb$, LEN(stringmathb$) - 2, 1) <> "." THEN stringmathb$ = "invalid number": RETURN
    IF LEFT$(stringmathb$, 1) = "-" THEN stringmathb$ = MID$(stringmathb$, 2)
    stringmathb$ = sm_sign$ + "$" + stringmathb$
    RETURN

    numeric_to_scientific:
    IF LEFT$(stringmathb$, 1) = "-" THEN stringmathb$ = MID$(stringmathb$, 2): n2sign$ = "-"
    IF INSTR(stringmathb$, ".") = 0 THEN exponentvalue&& = LEN(stringmathb$) - 1 ELSE exponentvalue&& = INSTR(stringmathb$, ".") - 2 ' Exponent is one less than number of digits for whole number an two less than the placement of the decimal point for a fraction.
    stringmathb$ = MID$(stringmathb$, 1, INSTR(stringmathb$, ".") - 1) + MID$(stringmathb$, INSTR(stringmathb$, ".") + 1)
    IF LEFT$(stringmathb$, 1) = "0" AND LEN(stringmathb$) > 1 OR exponentvalue&& = -1 THEN
        DO UNTIL LEFT$(stringmathb$, 1) <> "0" ' Remove leading zeros to consider rounding.
            stringmathb$ = MID$(stringmathb$, 2)
            exponentvalue&& = exponentvalue&& - 1
        LOOP
        esign$ = "-"
    ELSE
        esign$ = "+"
    END IF
    DO UNTIL RIGHT$(stringmathb$, 1) <> "0" ' Remove trailing zeros.
        stringmathb$ = MID$(stringmathb$, 1, LEN(stringmathb$) - 1)
    LOOP
    IF stringmathb$ = "" THEN stringmathb$ = "0": esign$ = "+": exponentvalue&& = 0
    stringmathb$ = LEFT$(stringmathb$, 1) + "." + MID$(stringmathb$, 2)
    IF stringmathb$ = "0." THEN n2sign$ = "": esign$ = "+"
    stringmathb$ = stringmathb$ + "e" + esign$ + LTRIM$(STR$(ABS(exponentvalue&&))) ' S.N formed here.
    IF stringmathb$ <> "overflow" THEN
        stringmathb$ = n2sign$ + stringmathb$
    END IF
    n2sign$ = "": esign$ = "": exponentvalue&& = 0
    RETURN

    scientific_to_numeric:
    IF INSTR(UCASE$(stringmathb$), "D") THEN MID$(stringmathb$, INSTR(UCASE$(stringmathb$), "D"), 1) = "e"
    IF MID$(stringmathb$, INSTR(stringmathb$, "e") + 2) = "0" THEN ' The numeric value is the number without the zero exponent.
        stringmathb$ = MID$(stringmathb$, 1, INSTR(stringmathb$, "e") - 1)
        IF RIGHT$(stringmathb$, 1) = "." THEN stringmathb$ = MID$(stringmathb$, 1, LEN(stringmathb$) - 1)
        RETURN
    ELSE
        IF LEFT$(stringmathb$, 1) = "-" THEN stn_sign$ = "-": stringmathb$ = MID$(stringmathb$, 2)
        stringmathb$ = MID$(stringmathb$, 1, INSTR(stringmathb$, ".") - 1) + MID$(stringmathb$, INSTR(stringmathb$, ".") + 1) ' Remove decimal point.
        stn_i& = INSTR(stringmathb$, "e") - 1 ' Length of the numric part.
        IF MID$(stringmathb$, INSTR(stringmathb$, "e") + 1, 1) = "-" THEN
            stringmathb$ = "." + STRING$(VAL(MID$(stringmathb$, stn_i& + 3)) - 1, "0") + MID$(stringmathb$, 1, stn_i&) ' Decimal point followed by exponent value in zeros added in front of numeric part.
        ELSE
            IF stn_i& - 1 > VAL(MID$(stringmathb$, stn_i& + 3)) THEN stn_point$ = "." ' - 1 for decimal place. Ex 2.034d+2 is 2034 here where 3 places to the right . could be moved before . disappears. > so no trailing decimal results.
            stringmathb$ = MID$(MID$(stringmathb$, 1, stn_i&), 1, VAL(MID$(stringmathb$, stn_i& + 3)) + 1) + stn_point$ + MID$(MID$(stringmathb$, 1, stn_i&), VAL(MID$(stringmathb$, stn_i& + 3)) + 2, stn_i& - VAL(MID$(stringmathb$, stn_i& + 3)) - 1) + STRING$(VAL(MID$(stringmathb$, stn_i& + 2)) - (stn_i& - 1), "0")
        END IF
    END IF
    IF stringmathb$ = "0" THEN stn_sign$ = ""
    stringmathb$ = stn_sign$ + stringmathb$
    stn_sign$ = "": stn_point$ = ""
    RETURN

    limit_round_convert:
    ' Try SN if whole number is too large (as it may be trailing zeros) or decimal is beyond limit.
    IF LEFT$(stringmathb$, 2) = ".0" AND LEN(stringmathb$) > limit&& + 1 OR INSTR(stringmathb$, ".") > limit&& + 1 OR INSTR(stringmathb$, ".") = 0 AND LEN(stringmathb$) > limit&& THEN
        IF limit&& > 1 THEN
            GOSUB numeric_to_scientific ' Retry as S.N.
            IF LEN(stringmathb$) > limit&& + 3 THEN ' Needs rounding.
                snotation$ = MID$(stringmathb$, INSTR(UCASE$(stringmathb$), "E"))
                exponentvalue&& = VAL(MID$(snotation$, 2)) ' Get positive or negative sign.
                snexponent$ = MID$(stringmathb$, INSTR(UCASE$(stringmathb$), "E") + 2)
                stringmathb$ = MID$(stringmathb$, 1, INSTR(UCASE$(stringmathb$), "E") - 1)
                '''IF LEN(stringmathb$) + LEN(snexponent$) > limit&& + 1 AND exponentvalue&& >= limit&& THEN BEEP
                IF exponentvalue&& >= limit&& THEN
                    stringmathb$ = MID$(stringmathb$, 1, exponentvalue&& + 3)
                ELSE
                    stringmathb$ = MID$(stringmathb$, 1, limit&& - LEN(snexponent$) + 2)
                END IF
                GOSUB string_rounding_method
                IF LEFT$(stringmathb$, 3) = "10." THEN
                    stringmathb$ = "1." + MID$(stringmathb$, 4)
                    ' Add one to the exponent.
                    FOR round_i& = LEN(snexponent$) TO 1 STEP -1
                        round_x$ = CHR$(ASC(MID$(snexponent$, round_i&, 1)) + 1)
                        IF round_x$ <> CHR$(47) THEN ' Decimal point + 1. Ignore.
                            IF round_x$ = CHR$(58) THEN
                                MID$(snexponent$, round_i&, 1) = "0": carry$ = "1"
                            ELSE
                                MID$(snexponent$, round_i&, 1) = round_x$: carry$ = "": EXIT FOR
                            END IF
                        END IF
                    NEXT
                    snexponent$ = carry$ + snexponent$: carry$ = ""
                END IF
                stringmathb$ = stringmathb$ + MID$(snotation$, 1, 2) + snexponent$
                IF LEN(snexponent$) + LEN(MID$(stringmathb$, 1, INSTR(UCASE$(stringmathb$), "E") - 1)) > limit&& + 1 THEN
                    stringmathb$ = "overflow"
                END IF
                exponentvalue&& = 0
            END IF
        ELSE
            IF INSTR(stringmathb$, ".") > 0 AND INSTR(stringmathb$, ".") <= limit&& THEN
                stringmathb$ = MID$(stringmathb$, 1, limit&& + 2)
                IF round_total% = -1 AND RIGHT$(stringmathb$, 1) > "4" THEN
                    GOSUB string_rounding_method
                ELSE
                    stringmathb$ = MID$(stringmathb$, 1, limit&& + 1)
                    IF show_rounding% THEN stringmathround$ = "r"
                END IF
            ELSE
                stringmathb$ = "overflow"
            END IF
        END IF
        RETURN
    END IF
    IF LEN(stringmathb$) > limit&& AND INSTR(stringmathb$, ".") = 0 OR LEN(stringmathb$) > limit&& + 1 AND INSTR(stringmathb$, ".") <> 0 THEN
        IF INSTR(stringmathb$, ".") = 0 THEN
            stringmathb$ = MID$(stringmathb$, 1, limit&& + 1)
        ELSE
            stringmathb$ = MID$(stringmathb$, 1, limit&& + 2)
        END IF
        GOSUB string_rounding_method
        IF LEN(stringmathb$) > limit&& + lrc_decimalpoint& THEN ' Ex: limit&& = 4 9999.9 1.e+4
            GOSUB numeric_to_scientific
        ELSE
            IF LEN(stringmathb$) > limit&& + lrc_decimalpoint& THEN stringmathb$ = "overflow"
        END IF
    END IF
    RETURN

    replace_decimal:
    IF addsubplace& THEN
        addsubx1$ = STRING$(addsubplace& - LEN(addsubx1$), "0") + addsubx1$
        addsubx1$ = MID$(addsubx1$, 1, LEN(addsubx1$) - addsubplace&) + "." + MID$(addsubx1$, LEN(addsubx1$) - addsubplace& + 1)
        DO UNTIL RIGHT$(addsubx1$, 1) <> "0" ' Remove trailing zeros in a decimal sum.
            addsubx1$ = MID$(addsubx1$, 1, LEN(addsubx1$) - 1)
            addsubplace& = addsubplace& - 1
        LOOP
        IF RIGHT$(addsubx1$, 1) = "." THEN addsubx1$ = MID$(addsubx1$, 1, LEN(addsubx1$) - 1) ' Number is now an integer.
    END IF
    RETURN

    string_rounding_method:
    IF INSTR(stringmathb$, ".") THEN lrc_decimalpoint& = 1 ELSE lrc_decimalpoint& = 0
    IF MID$(stringmathb$, LEN(stringmathb$), 1) > "4" THEN
        FOR round_i& = LEN(stringmathb$) - 1 TO 1 STEP -1
            round_x$ = CHR$(ASC(MID$(stringmathb$, round_i&, 1)) + 1)
            IF round_x$ <> CHR$(47) THEN ' Decimal point + 1. Ignore.
                IF round_x$ = CHR$(58) THEN
                    MID$(stringmathb$, round_i&, 1) = "0": carry$ = "1"
                ELSE
                    MID$(stringmathb$, round_i&, 1) = round_x$: carry$ = "": EXIT FOR
                END IF
            END IF
        NEXT
        stringmathb$ = carry$ + MID$(stringmathb$, 1, LEN(stringmathb$) - 1): carry$ = ""
        IF show_rounding% THEN stringmathround$ = "R"
    ELSE
        stringmathb$ = MID$(stringmathb$, 1, LEN(stringmathb$) - 1)
        IF show_rounding% THEN stringmathround$ = "r"
    END IF

    IF lrc_decimalpoint& THEN
        DO UNTIL RIGHT$(stringmathb$, 1) <> "0"
            stringmathb$ = MID$(stringmathb$, 1, LEN(stringmathb$) - 1)
        LOOP
        IF stringmathb$ = "" OR stringmathb$ = "." THEN stringmathb$ = "0": lrc_decimalpoint& = 0
        IF RIGHT$(stringmathb$, 1) = "." AND exponentvalue&& = 0 THEN
            stringmathb$ = MID$(stringmathb$, 1, LEN(stringmathb$) - 1): lrc_decimalpoint& = 0
        END IF
    END IF
    RETURN
END SUB


I set the default limit&& (number of digits to display) to 1700.

You can unremark the scientific notation variable, if you want results in SN.

Have a great weekend!

Pete
Reply
#22
thanks Pete Smile
it works as advertised, you are not the first person that has tried to fix the annoyance of floating-point round errors, just search for "exact real arithmetic"
Reply
#23
@Jack aren't you the one who was giving me pointers in my string math on the old forum? Eg doing square roots with string math and Fibonacci sequence from inverse with the 999... 8 9999 thing?

We do string math because regular math sucks either in precision or decimal point crap.
b = b + ...
Reply
#24
bplus, the reason I posted Treebeard's code was so that SierraKen might consider using string-math in his calculator, I only ported the basic 4 arithmetic functions, just enough to illustrate
Reply
#25
Updated to include Sqr, Log, Exp and trig functions
Reply
#26
(08-08-2022, 06:12 PM)Jack Wrote: Updated to include Sqr, Log, Exp and trig functions

Are these (Log, Exp and trig functions, I know about SQR as we worked on it at the old forum) using String math with the Taylor or Maclaurin Series?
b = b + ...
Reply
#27
bplus, I think so
the differences are that these string math routines are not mine, I only adapted them to QB64 also the sqr function seems to extract the root longhand rather than using the newton-raphson
Reply




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