So I tried this new improved division code I created in the pi routine Jack provided, and wow, a 700% speed improvement! That makes it 500%+ faster than that same pi routine running with Treebeard's string math.
From the pi thread, I commented about the improvements...
"Basically what I did was to shortcut zero and 1 divisors, chop out leading zeros in small decimal numbers making less digits to calculate, estimate the mult loop by using just the first one or two digits of the divisor and the dividend or remainder so it usually only takes two tries to get the right multiplier before subtracting to obtain the remainder and, of course, working with chunks of numbers with multiplication and subtraction in the long division process.
I knew it would be faster, I'm just amazed it's so much faster.
Now I'm wondering how much faster it could be if I switched from string concatenation to fixed string replacement? I did that once with a c keyboard WP routine (about the only complicated C/C++ prog I've ever written) and the speed increase was pretty impressive. Converting for string math might be a bit of a challenge, and if too many conditions need to be added, it might end up being a push."
So this code was added to that pi routine, but you can try the it out here as a divison calculator by inputting a dividend and divisor. It will validate input, but I left out my conversion of scientific notation to numerical expresion for this demo, so don't input SI.
It has a variable named: BETATEST%. Set it to ZERO to avoid all the screen notes, SLEEP between loops, and just get the results. I kept betatest% = -1 for this demo, to show the divison steps in progress.
Increase or decrease the limit&& variable to control the number of digits displayed. Note: for this demo, I did not include my rounding routie to round the last digit displayed.
So while my previous string routine was accurate for large numbers, this routine is looking to be both accurate and fast. I think it's fast enough now to be to calculate numbers with several hundreds of digits to sevreral hundreds of places almost instantaneously!
As for beta testing, that's another workhorse in the making. I will need to try some huge numbers out on n online precison calculator later. Of course if anyone spots any bugs, let me know, and I'll look into it. Maybe soon I can bump this baby up to a work in progress.
Thanks to Jack for getting me motivated to look further into this project.
Pete
PS Here is the routine used in the pi calculations: https://staging.qb64phoenix.com/showthre...95#pid6495
From the pi thread, I commented about the improvements...
"Basically what I did was to shortcut zero and 1 divisors, chop out leading zeros in small decimal numbers making less digits to calculate, estimate the mult loop by using just the first one or two digits of the divisor and the dividend or remainder so it usually only takes two tries to get the right multiplier before subtracting to obtain the remainder and, of course, working with chunks of numbers with multiplication and subtraction in the long division process.
I knew it would be faster, I'm just amazed it's so much faster.
Now I'm wondering how much faster it could be if I switched from string concatenation to fixed string replacement? I did that once with a c keyboard WP routine (about the only complicated C/C++ prog I've ever written) and the speed increase was pretty impressive. Converting for string math might be a bit of a challenge, and if too many conditions need to be added, it might end up being a push."
So this code was added to that pi routine, but you can try the it out here as a divison calculator by inputting a dividend and divisor. It will validate input, but I left out my conversion of scientific notation to numerical expresion for this demo, so don't input SI.
It has a variable named: BETATEST%. Set it to ZERO to avoid all the screen notes, SLEEP between loops, and just get the results. I kept betatest% = -1 for this demo, to show the divison steps in progress.
Increase or decrease the limit&& variable to control the number of digits displayed. Note: for this demo, I did not include my rounding routie to round the last digit displayed.
So while my previous string routine was accurate for large numbers, this routine is looking to be both accurate and fast. I think it's fast enough now to be to calculate numbers with several hundreds of digits to sevreral hundreds of places almost instantaneously!
As for beta testing, that's another workhorse in the making. I will need to try some huge numbers out on n online precison calculator later. Of course if anyone spots any bugs, let me know, and I'll look into it. Maybe soon I can bump this baby up to a work in progress.
Thanks to Jack for getting me motivated to look further into this project.
Code: (Select All)
WIDTH 160, 42
_SCREENMOVE 0, 0
DIM SHARED limit&&, betatest%
limit&& = 32: betatest% = 1
DO
LINE INPUT "Dividend: "; stringmatha$
LINE INPUT "Divisor: "; stringmathb$
CALL sm(stringmatha$, stringmathb$, runningtotal$)
IF runningtotal$ <> "invalid" THEN COLOR 14, 1: PRINT "Quotent = "; runningtotal$;: COLOR 7, 0: PRINT: PRINT "---------------------------------": PRINT
LOOP
SUB sm (stringmatha$, stringmathb$, runningtotal$)
DIM AS _INTEGER64 a, c, aa, cc, s, ss
validate$ = stringmatha$: GOSUB validate_string_number
IF validate$ = "invalid number" THEN PRINT "Invalid number entry. Redo...": runningtotal$ = "invalid": EXIT SUB
validate$ = stringmathb$: GOSUB validate_string_number
IF validate$ = "invalid number" THEN PRINT "Invalid number entry. Redo...": runningtotal$ = "invalid": EXIT SUB
GOSUB string_divide_new
EXIT SUB
string_divide_new:
q$ = "": divisor$ = stringmathb$: dividend$ = stringmatha$
DO ' Falx loop.
'Strip off neg(s) and determine quotent sign.
IF LEFT$(divisor$, 1) = "-" THEN divisor$ = MID$(divisor$, 2): q$ = "-"
IF LEFT$(dividend$, 1) = "-" THEN dividend$ = MID$(dividend$, 2): IF q$ = "-" THEN q$ = "" ELSE q$ = "-"
' Quick results for divisor 1 or 0.
IF divisor$ = "0" THEN q$ = "0": EXIT DO
IF divisor$ = "1" THEN q$ = dividend$: EXIT DO
IF dividend$ = "0" THEN q$ = "Division by zero not possible.": EXIT DO
' Determine decimal direction. -1 to left, +1 to right.
gl% = 0: string_compare divisor$, dividend$, gl%
IF betatest% AND gl% = 1 THEN PRINT divisor$; " > "; dividend$; " Move decimal to the left"
IF betatest% AND gl% = 0 THEN PRINT divisor$; " = "; dividend$
IF betatest% AND gl% = -1 THEN PRINT divisor$; " < "; dividend$; " Move deciml to the right."
IF gl% = 1 THEN ' Divisor is larger than dividend so decimal moves to the left.
div_decimal% = -1 ' Move decimal point to the left.
ELSEIF gl% = -1 THEN
div_decimal% = 1 ' Move decimal point to the right.
ELSE
' Divisor and dividend are the same number.
q$ = q$ + "1": EXIT DO
END IF
divisor_ratio_dividend% = gl%
' Strip off decimal point(s) and determine places in these next 2 routines.
dp&& = 0: dp2&& = 0: j2&& = 0
temp&& = INSTR(divisor$, ".")
IF temp&& THEN
divisor$ = MID$(divisor$, 1, temp&& - 1) + MID$(divisor$, temp&& + 1)
IF temp&& = 1 THEN
DO UNTIL LEFT$(divisor$, 1) <> "0" ' Strip off any leading zeros on divisor only.
divisor$ = MID$(divisor$, 2)
dp&& = dp&& + 1
LOOP
dp&& = dp&& + 1
ELSE
dp&& = -(temp&& - 2)
END IF
ELSE
dp&& = -(LEN(divisor$) - 1)
END IF
temp&& = INSTR(dividend$, ".")
IF temp&& THEN
dividend$ = MID$(dividend$, 1, temp&& - 1) + MID$(dividend$, temp&& + 1)
IF temp&& = 1 THEN
DO UNTIL LEFT$(dividend$, 1) <> "0" ' Strip off any leading zeros on divisor only.
dividend$ = MID$(dividend$, 2)
dp2&& = dp2&& + 1
LOOP
dp2&& = dp2&& + 1
ELSE
dp2&& = -(temp&& - 2)
END IF
ELSE
dp2&& = -(LEN(dividend$) - 1)
END IF
IF betatest% THEN COLOR 11: PRINT "Divisor decimal moves "; LTRIM$(STR$(dp&&)); ". Dividend decimal moves"; LTRIM$(STR$(dp2&&)); ". Quotent decimal ABS("; LTRIM$(STR$(dp&&)); " - "; LTRIM$(STR$(dp2&&)); ") =";: COLOR 14: PRINT ABS(dp&& - dp2&&);: COLOR 11: PRINT "+ any adjustment.": COLOR 7
dp&& = ABS(dp&& - dp2&&)
IF betatest% THEN PRINT "Divisor 1st# = "; MID$(divisor$, 1, 1); " Remainder 1st# = "; MID$(dividend$, 1, 1)
' Adjust decimal place for instances when divisor is larger than remainder.
IF MID$(divisor$, 1, 1) > MID$(dividend$, 1, 1) THEN
dp&& = dp&& - div_decimal%
IF betatest% THEN PRINT "Larger divisor, so move quotent decimal one place back to: ";: COLOR 14: PRINT LTRIM$(STR$(dp&&)): COLOR 7
ELSEIF MID$(divisor$, 1, 1) = MID$(dividend$, 1, 1) THEN
IF divisor_ratio_dividend% = 1 THEN
dp&& = dp&& - div_decimal%
IF betatest% THEN PRINT "Larger divisor, so move quotent decimal one place back to: ";: COLOR 14: PRINT LTRIM$(STR$(dp&&)): COLOR 7
ELSE
IF betatest% THEN PRINT "Smaller divisor, so no quotent decimal place adjustment needed. Quotent decimal place = ";: COLOR 14: PRINT LTRIM$(STR$(dp&&)): COLOR 7
END IF
ELSE
IF betatest% THEN PRINT "Smaller divisor, so no quotent decimal place adjustment needed. Quotent decimal place = ";: COLOR 14: PRINT LTRIM$(STR$(dp&&)): COLOR 7
END IF
origdividend$ = dividend$
' Determine length of divisor and dividend to begin initial long divison step.
gl% = 2: string_compare divisor$, MID$(dividend$, 1, LEN(divisor$)) + STRING$(LEN(divisor$) - LEN(dividend$), "0"), gl%
divisor_ratio_dividend% = gl%
IF gl% = 1 AND MID$(dividend$, 1, 1) <> "0" THEN
dividend$ = MID$(dividend$, 1, LEN(divisor$) + 1) + STRING$(LEN(divisor$) + 1 - LEN(dividend$), "0")
ELSE
dividend$ = MID$(dividend$, 1, LEN(divisor$)) + STRING$(LEN(divisor$) - LEN(dividend$), "0")
END IF
' Long divison loop. Mult and subtraction of dividend and remainder.
k&& = 0
IF betatest% THEN PRINT "Begin long divison loop..."
DO
SELECT CASE MID$(divisor$, 1, 1)
CASE IS < MID$(dividend$, 1, 1)
adj_rem_len% = 0
CASE IS = MID$(dividend$, 1, 1)
gl% = 2: string_compare divisor$, MID$(dividend$, 1, LEN(divisor$)), gl%
IF gl% = 1 THEN adj_rem_len% = 1 ELSE adj_rem_len% = 0
CASE IS > MID$(dividend$, 1, 1)
adj_rem_len% = 1
END SELECT
IF j2&& = 0 THEN j2&& = LEN(divisor$) + adj_rem_len%
DO
IF LEN(divisor$) > LEN(dividend$) THEN
w3&& = 0: runningtotal$ = dividend$: stringmathb$ = "0"
IF betatest% THEN PRINT: COLOR 3: PRINT "Divisor is larger so "; dividend$; " \ "; divisor$; " =";: COLOR 5: PRINT w3&&: COLOR 7
EXIT DO
END IF
IF LEN(divisor$) = LEN(dividend$) THEN
gl% = 2: string_compare divisor$, dividend$, gl%
IF gl% = 1 THEN
w3&& = 0: runningtotal$ = dividend$: stringmathb$ = "0"
IF betatest% THEN COLOR 9: PRINT "Length of divisor is the same as remainder but remainder is smaller so w3&& = ";: COLOR 5: PRINT "0": COLOR 7
EXIT DO
END IF
END IF
SELECT CASE LEN(dividend$)
CASE IS > 2
w3&& = VAL(MID$(dividend$, 1, 2 + adj_rem_len%)) \ VAL(MID$(divisor$, 1, 2))
IF betatest% THEN PRINT MID$(dividend$, 1, 2 + adj_rem_len%); " \ "; MID$(divisor$, 1, 2); " =";
CASE ELSE
w3&& = VAL(MID$(dividend$, 1, 1 + adj_rem_len%)) \ VAL(MID$(divisor$, 1, 1))
IF betatest% THEN PRINT MID$(dividend$, 1, 1 + adj_rem_len%); " \ "; MID$(divisor$, 1, 1); " =";
END SELECT
IF betatest% THEN COLOR 5: PRINT " " + LTRIM$(STR$(w3&&));: COLOR 7: PRINT ". Begin mult est. at or one above this number."
IF w3&& < 9 THEN w3&& = w3&& + 1 ELSE IF w3&& = 10 THEN w3&& = 9
DO
stringmatha$ = divisor$: stringmathb$ = LTRIM$(STR$(w3&&))
GOSUB string_multiply_new
gl% = 2: string_compare runningtotal$, dividend$, gl%
IF gl% <= 0 OR w3&& = 0 THEN EXIT DO
IF betatest% THEN COLOR 8: PRINT "Mult loop:"; w3&&; "* "; divisor$; " = "; runningtotal$: COLOR 7
w3&& = w3&& - 1
LOOP
stringmatha$ = dividend$: stringmathb$ = runningtotal$
operator$ = "-": GOSUB string_add_subtract_new
EXIT DO
LOOP
IF betatest% THEN PRINT LTRIM$(STR$(w3&&)); " * "; divisor$; " = "; stringmathb$; " | "; stringmatha$; " - "; stringmathb$; " = "; runningtotal$; " Remainder and drop-down = ";
j2&& = j2&& + 1
drop$ = "0": MID$(drop$, 1, 1) = MID$(origdividend$, j2&&, 1)
IF runningtotal$ <> "0" THEN remainder$ = runningtotal$ ELSE remainder$ = ""
dividend$ = remainder$ + drop$
w3$ = LTRIM$(STR$(w3&&))
temp$ = ""
IF div_decimal% = -1 THEN
IF dp&& AND k&& = 0 THEN
q$ = q$ + "." + STRING$(dp&& - 1, "0")
IF w3&& = 0 THEN w3$ = ""
END IF
END IF
IF div_decimal% >= 0 THEN
IF dp&& = k&& THEN
temp$ = "."
END IF
END IF
q$ = q$ + w3$ + temp$
IF betatest% AND remainder$ = "" THEN betatemp$ = CHR$(34) + CHR$(34) ELSE IF betatest% THEN betatemp$ = remainder$
IF betatest% AND MID$(origdividend$, j2&&, 1) = "" THEN betatemp2$ = CHR$(34) + CHR$(34) ELSE IF betatest% THEN betatemp2$ = MID$(origdividend$, j2&&, 1)
IF betatest% THEN PRINT dividend$; " ("; betatemp$; " + "; drop$; ") at:"; j2&&; "of "; origdividend$; " Loop"; k&& + 1; "Quotent = ";: COLOR 14, 4: PRINT q$;: COLOR 7, 0: PRINT: SLEEP
' Check to terminate
IF div_decimal% = -1 THEN
' Decimal to left.
IF remainder$ = "" AND MID$(origdividend$, j2&&, 1) = "" OR j2&& = limit&& THEN EXIT DO
ELSE
' Decimal to right.
IF remainder$ = "" AND MID$(origdividend$, j2&&, 1) = "" AND k&& >= dp&& OR j2&& = limit&& THEN EXIT DO
END IF
IF INKEY$ = " " THEN EXIT DO
k&& = k&& + 1
LOOP
EXIT DO
LOOP
IF RIGHT$(q$, 1) = "." THEN runningtotal$ = MID$(q$, 1, LEN(q$) - 1) ELSE runningtotal$ = q$
RETURN
string_add_subtract_new:
a1$ = stringmatha$: b1$ = stringmathb$
s = 18: i&& = 0: c = 0
a$ = stringmatha$: b$ = stringmathb$: op$ = operator$
IF op$ = "-" THEN
IF LEFT$(b$, 1) = "-" THEN b$ = MID$(b$, 2) ELSE b$ = "-" + b$
END IF
IF INSTR(a$, ".") <> 0 OR INSTR(b$, ".") <> 0 THEN
decimal% = -1
IF INSTR(a$, ".") <> 0 THEN
dec_a&& = LEN(MID$(a$, INSTR(a$, ".") + 1))
a$ = MID$(a$, 1, INSTR(a$, ".") - 1) + MID$(a$, INSTR(a$, ".") + 1)
END IF
IF INSTR(b$, ".") <> 0 THEN
dec_b&& = LEN(MID$(b$, INSTR(b$, ".") + 1))
b$ = MID$(b$, 1, INSTR(b$, ".") - 1) + MID$(b$, INSTR(b$, ".") + 1)
END IF
' Line up decimal places by inserting trailing zeros.
IF dec_b&& > dec_a&& THEN
j&& = dec_b&&
a$ = a$ + STRING$(dec_b&& - dec_a&&, "0")
ELSE
j&& = dec_a&&
b$ = b$ + STRING$(dec_a&& - dec_b&&, "0")
END IF
END IF
IF LEFT$(a$, 1) = "-" OR LEFT$(b$, 1) = "-" THEN
IF LEFT$(a$, 1) = "-" AND LEFT$(b$, 1) = "-" THEN
sign$ = "": a$ = MID$(a$, 2): b$ = MID$(b$, 2)
ELSE
IF LEFT$(a$, 1) = "-" THEN a$ = MID$(a$, 2): sign_a$ = "-"
IF LEFT$(b$, 1) = "-" THEN b$ = MID$(b$, 2): sign_b$ = "-"
IF LEFT$(a1$, 1) = "-" THEN a1_x$ = MID$(a1$, 2) ELSE a1_x$ = a1$
IF LEFT$(b1$, 1) = "-" THEN b1_x$ = MID$(b1$, 2) ELSE b1_x$ = b1$
string_compare a1_x$, b1_x$, gl%
IF gl% < 0 THEN
IF LEN(sign_b$) THEN sign$ = "-": SWAP a$, b$
ELSE
IF LEN(sign_a$) THEN sign$ = "-": SWAP sign_a$, sign_b$
END IF
END IF
END IF
z$ = ""
' Addition and subtraction of digits.
DO
i&& = i&& + s
x1$ = MID$(a$, LEN(a$) - i&& + 1, s)
x2$ = MID$(b$, LEN(b$) - i&& + 1, s)
IF LEN(x2$) > LEN(x1$) THEN SWAP x1$, x2$
a = VAL(sign_a$ + x1$) + VAL(sign_b$ + x2$) + c
IF x1$ + x2$ = "" AND c = 0 THEN EXIT DO
c = 0
IF a > VAL(STRING$(s, "9")) THEN a = a - 10 ^ s: c = 1
IF a < 0 THEN a = a + 10 ^ s: c = -1 ' a will never be less than 0.
tmp$ = LTRIM$(STR$(a))
z$ = STRING$(LEN(x1$) - LEN(tmp$), "0") + tmp$ + z$
LOOP
IF decimal% THEN
z$ = MID$(z$, 1, LEN(z$) - j&&) + "." + MID$(z$, LEN(z$) - j&& + 1)
END IF
' Remove any leading zeros.
DO
IF LEFT$(z$, 1) = "0" THEN z$ = MID$(z$, 2) ELSE EXIT DO
LOOP
IF z$ = "" OR z$ = "0" THEN z$ = "0" ELSE z$ = LEFT$(sign$, 1) + z$
runningtotal$ = z$
sign$ = "": sign_a$ = "": sign_b$ = "": i&& = 0: j&& = 0: decimal% = 0: c = 0
RETURN
string_multiply_new:
z$ = "": sign$ = "": mult&& = 0: h&& = 0: i&& = 0: j&& = 0: c = 0: decimal% = 0
zz$ = "": ii&& = 0: jj&& = 0
s = 8: ss = 18
a$ = stringmatha$: b$ = stringmathb$
IF INSTR(a$, "-") <> 0 OR INSTR(b$, "-") <> 0 THEN
IF INSTR(a$, "-") <> 0 AND INSTR(b$, "-") <> 0 THEN
a$ = MID$(a$, 2): b$ = MID$(b$, 2)
ELSE
IF INSTR(a$, "-") <> 0 THEN a$ = MID$(a$, 2) ELSE b$ = MID$(b$, 2)
sign$ = "-"
END IF
END IF
IF INSTR(a$, ".") <> 0 OR INSTR(b$, ".") <> 0 THEN
decimal% = -1
IF INSTR(a$, ".") <> 0 THEN
dec_a&& = LEN(MID$(a$, INSTR(a$, ".") + 1))
a$ = MID$(a$, 1, INSTR(a$, ".") - 1) + MID$(a$, INSTR(a$, ".") + 1)
END IF
IF INSTR(b$, ".") <> 0 THEN
dec_b&& = LEN(MID$(b$, INSTR(b$, ".") + 1))
b$ = MID$(b$, 1, INSTR(b$, ".") - 1) + MID$(b$, INSTR(b$, ".") + 1)
END IF
END IF
IF LEN(a$) < LEN(b$) THEN SWAP a$, b$ ' Needed so x1$ is always the largest for leading zero replacements.
' Multiplication of digits.
DO
h&& = h&& + s: i&& = 0
x2$ = MID$(b$, LEN(b$) - h&& + 1, s)
DO
i&& = i&& + s
x1$ = MID$(a$, LEN(a$) - i&& + 1, s)
a = VAL(x1$) * VAL(x2$) + c
c = 0
tmp$ = LTRIM$(STR$(a))
IF LEN(tmp$) > s THEN c = VAL(MID$(tmp$, 1, LEN(tmp$) - s)): tmp$ = MID$(tmp$, LEN(tmp$) - s + 1)
z$ = STRING$(LEN(x1$) - LEN(tmp$), "0") + tmp$ + z$
LOOP UNTIL i&& >= LEN(a$) AND c = 0
jj&& = jj&& + 1
IF jj&& > 1 THEN
ii&& = 0: cc = 0
aa$ = holdaa$
bb$ = z$ + STRING$((jj&& - 1) * s, "0")
' Addition only of digits.
DO
ii&& = ii&& + ss
xx1$ = MID$(aa$, LEN(aa$) - ii&& + 1, ss)
xx2$ = MID$(bb$, LEN(bb$) - ii&& + 1, ss)
IF LEN(xx1$) < LEN(xx2$) THEN SWAP xx1$, xx2$
aa = VAL(xx1$) + VAL(xx2$) + cc
IF xx1$ + xx2$ = "" AND cc = 0 THEN EXIT DO ' Prevents leading zeros.
cc = 0
IF aa > VAL(STRING$(ss, "9")) THEN aa = aa - 10 ^ ss: cc = 1
tmp$ = LTRIM$(STR$(aa))
zz$ = STRING$(LEN(xx1$) - LEN(tmp$), "0") + tmp$ + zz$
LOOP
DO WHILE LEFT$(zz$, 1) = "0"
IF LEFT$(zz$, 1) = "0" THEN zz$ = MID$(zz$, 2)
LOOP
IF zz$ = "" THEN zz$ = "0"
holdaa$ = zz$
ELSE
holdaa$ = z$ + STRING$(jj&& - 1, "0")
END IF
z$ = "": zz$ = ""
LOOP UNTIL h&& >= LEN(b$)
z$ = holdaa$
IF decimal% THEN
DO UNTIL LEN(z$) >= dec_a&& + dec_b&&
z$ = "0" + z$
LOOP
z$ = MID$(z$, 0, LEN(z$) - (dec_a&& + dec_b&& - 1)) + "." + MID$(z$, LEN(z$) - (dec_a&& + dec_b&&) + 1)
DO UNTIL RIGHT$(z$, 1) <> "0" AND RIGHT$(z$, 1) <> "."
z$ = MID$(z$, 1, LEN(z$) - 1)
LOOP
END IF
IF STRING$(LEN(z$), "0") = z$ OR z$ = "" OR z$ = "0" THEN z$ = "0" ELSE z$ = sign$ + z$
decimal% = 0: sign$ = ""
runningtotal$ = z$
RETURN
validate_string_number:
vsn_negcnt& = 0: vsn_poscnt& = 0: vsn_depresent& = 0: decimalcnt& = 0: vsn_numberpresent& = 0: vsn_zerospresent& = 0
IF LEFT$(validate$, 1) = "-" THEN validate$ = MID$(validate$, 2): sm_sign$ = "-" ELSE sm_sign$ = ""
IF LEFT$(validate$, 1) = "+" THEN IF sm_sign$ <> "-" THEN validate$ = MID$(validate$, 2) ELSE validate$ = "invalid number": RETURN
IF INSTR(UCASE$(validate$), "D") OR INSTR(UCASE$(validate$), "E") THEN ' Evaluate for Scientific Notation.
FOR sm_i& = 1 TO LEN(validate$)
validatenum$ = MID$(UCASE$(validate$), sm_i&, 1)
SELECT CASE validatenum$
CASE "+"
IF vsn_depresent& THEN vsn_poscnt& = vsn_poscnt& + 1 ELSE validate$ = "invalid number": RETURN
CASE "-"
IF vsn_depresent& THEN vsn_negcnt& = vsn_negcnt& + 1 ELSE validate$ = "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$(validate$, 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 validate$ = MID$(validate$, 1, 1) + "." + MID$(validate$, 2) ' Standardize "."
IF vsn_numberpresent& = 0 OR vsn_negcnt& = 1 AND vsn_poscnt& = 1 OR decimalcnt& > 1 OR INSTR(validate$, ".") <> 2 THEN validate$ = "invalid number": RETURN
vsn_depresent& = INSTR(validate$, "e")
sm_x$ = MID$(validate$, vsn_depresent& + 1, 1) ' Standardize exponent "+" these two lines.
IF sm_x$ <> "+" AND sm_x$ <> "-" THEN validate$ = MID$(validate$, 1, vsn_depresent&) + "+" + MID$(validate$, vsn_depresent& + 1)
IF MID$(validate$, vsn_depresent& + 2, 1) = "0" THEN
IF MID$(validate$, vsn_depresent& + 3, 1) <> "" THEN validate$ = "invalid number": RETURN ' No leading zeros allowed in exponent notation.
END IF
jjed& = INSTR(validate$, "e") ' Get position of notation.
valexpside$ = MID$(validate$, jjed&) ' These two lines break up into number and notation
validate$ = MID$(validate$, 1, jjed& - 1) ' validate$ is +- single digit whole number, decimal point and decimal number. valexpside$ is notation, sign and exponent.
DO UNTIL RIGHT$(validate$, 1) <> "0" ' Remove any trailing zeros for number. Example 1.0d3 or 1.0000d3, etc.
validate$ = MID$(validate$, 1, LEN(validate$) - 1)
LOOP
IF VAL(MID$(validate$, 1, INSTR(validate$, ".") - 1)) = 0 THEN
IF RIGHT$(validate$, 1) = "." THEN
validate$ = "0.e+0" ' Handles all types of zero entries.
ELSE
validate$ = "invalid number": RETURN
END IF
RETURN
END IF
validate$ = sm_sign$ + validate$ + valexpside$
RETURN
ELSE
FOR sm_i& = 1 TO LEN(validate$)
validatenum$ = MID$(validate$, sm_i&, 1)
SELECT CASE validatenum$
CASE "."
decimalcnt& = decimalcnt& + 1
CASE "0"
vsn_zerospresent& = -1
CASE "1" TO "9"
vsn_numberpresent& = -1
CASE "$"
CASE ELSE
validate$ = "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
validate$ = "invalid number": RETURN
END IF
REM IF INSTR(validate$, "$") THEN GOSUB currency_validate
IF INSTR(validate$, ",") THEN
REM GOSUB comma_validation
IF validate$ = "invalid number" THEN RETURN
REM GOSUB comma_removal
END IF
IF RIGHT$(validate$, 1) = "." THEN validate$ = MID$(validate$, 1, LEN(validate$) - 1)
DO UNTIL LEFT$(validate$, 1) <> "0" ' Strip off any leading zeros.
validate$ = MID$(validate$, 2)
LOOP
validate$ = sm_sign$ + validate$
IF INSTR(validate$, ".") THEN
DO UNTIL RIGHT$(validate$, 1) <> "0" ' Strip off any trailing zeros in a decimal.
validate$ = MID$(validate$, 1, LEN(validate$) - 1)
LOOP
END IF
IF RIGHT$(validate$, 1) = "." THEN validate$ = MID$(validate$, 1, LEN(validate$) - 1)
IF vsn_numberpresent& = 0 THEN
IF vsn_zerospresent& THEN
validate$ = "0"
ELSE
validate$ = "invalid number"
END IF
END IF
END IF
RETURN
END SUB
SUB string_compare (stringmatha$, stringmathb$, gl%)
compa$ = stringmatha$: compb$ = stringmathb$ ' So original variables do not get changed.
DO
WHILE -1 ' Falx loop.
IF gl% = 2 THEN EXIT WHILE ' For bypassing sign and decimal adjustments when only positive non-decimal numbers are being evaluated.
' Remove trailing zeros after a decimal point.
IF INSTR(compa$, ".") THEN
DO UNTIL RIGHT$(compa$, 1) <> "0" AND RIGHT$(compa$, 1) <> "." AND RIGHT$(compa$, 1) <> "-"
compa$ = MID$(compa$, 1, LEN(compa$) - 1)
LOOP
END IF
IF INSTR(compb$, ".") THEN
DO UNTIL RIGHT$(compb$, 1) <> "0" AND RIGHT$(compb$, 1) <> "." AND RIGHT$(compb$, 1) <> "-"
compb$ = MID$(compb$, 1, LEN(compb$) - 1)
LOOP
END IF
IF MID$(compa$, 1, 2) = "-0" OR compa$ = "" OR compa$ = "-" THEN compa$ = "0"
IF MID$(compb$, 1, 2) = "-0" OR compb$ = "" OR compb$ = "-" THEN compb$ = "0"
' A - and +
IF LEFT$(compa$, 1) = "-" THEN j% = -1
IF LEFT$(compb$, 1) = "-" THEN k% = -1
IF k% = 0 AND j% THEN gl% = -1: EXIT DO
IF j% = 0 AND k% THEN gl% = 1: EXIT DO
' A decimal and non-decimal.
j% = INSTR(compa$, ".")
k% = INSTR(compb$, ".")
IF j% = 0 AND k% THEN
IF compa$ = "0" THEN gl% = -1 ELSE gl% = 1
EXIT DO
END IF
IF k% = 0 AND j% THEN
IF compb$ = "0" THEN gl% = 1 ELSE gl% = -1
EXIT DO
END IF
' Both decimals.
IF j% THEN
SELECT CASE INSTR(compa$, ".")
CASE IS > INSTR(compb$, ".")
gl% = 1
CASE IS = INSTR(compb$, ".")
IF compa$ = compb$ THEN
gl% = 0
ELSEIF compa$ < compb$ THEN gl% = -1
ELSE
gl% = 1
END IF
CASE IS < INSTR(compb$, ".")
gl% = -1
END SELECT
EXIT DO
END IF
EXIT WHILE
WEND
' Remove leading zeros if any.
DO UNTIL LEFT$(compa$, 1) <> "0"
compa$ = MID$(compa$, 2)
LOOP
IF compa$ = "" THEN compa$ = "0"
DO UNTIL LEFT$(compb$, 1) <> "0"
compb$ = MID$(compb$, 2)
LOOP
IF compb$ = "" THEN compb$ = "0"
' Both positive or both negative whole numbers.
SELECT CASE LEN(compa$)
CASE IS < LEN(compb$)
gl% = -1
CASE IS = LEN(compb$)
IF compa$ = compb$ THEN
gl% = 0
ELSEIF compa$ > compb$ THEN gl% = 1
ELSEIF compa$ < compb$ THEN gl% = -1
END IF
CASE IS > LEN(compb$)
gl% = 1
END SELECT
EXIT DO
LOOP
END SUBPete
PS Here is the routine used in the pi calculations: https://staging.qb64phoenix.com/showthre...95#pid6495