DosTips.com

Code: Select all

@echo off
echo.
:: catch missing parameters
if "%3"=="" goto help
if "%2"=="" goto help
if "%1"=="" goto help
:: check for positive integers
if not %1 GTR 0 goto help
if not %2 GTR 0 goto help
if not %3 GTR 0 goto help

goto :continue

:help
echo You need three parameters, Top Divisor, Bottom Divisor and ^# of decimal places
echo Example: %0 387 41 20, will divide 387 by 41 out to 20 decimal places. Now you try.
echo Tip: You cannot use a zero "0" for any parameter, all parm's must be positive integers.
goto end

:continue
setlocal enableextensions enabledelayedexpansion

   :: all Variables are self explained 
    set /a TopDiv=%1
    set /a BotDiv=%2
    set /a Precis=%3 + 1
    set /a DivRsl=TopDiv / BotDiv
    set Solution=%TopDiv% / %BotDiv%=%DivRsl%.
  
:DivideMe   
    set /a TopDiv=(TopDiv - DivRsl * BotDiv) * 10
    if "%TopDiv%"=="0" goto Finished
    set /a DivRsl=TopDiv / BotDiv
    set /a Precis=Precis - 1
    if "%Precis%"=="0" goto Finished
    set Solution=%Solution%%DivRsl%
    goto DivideMe
   
:Finished
    for /f "tokens=1-3* delims==."  %%a in ('echo "!Solution!"') do (
      set Problem=%%a
      set Answer=%%b.%%c
      echo The solution to !Problem:~1! is !Answer:~0,-1!
   )
   
endlocal

:end
echo.

Code: Select all

divide_fast_orig.cmd 1 314159265 40

The solution to 1 / 314159265 is 0.0000000031-5-3-6-1-4-14-66125042455-544362-5-1-5-50-4

Code: Select all

@echo off
setlocal EnableDelayedExpansion

:: catch missing parameters
if "%3"=="" goto help

:: check for positive integers
if %1 GTR 0 if %2 GTR 0 if %3 GTR 0 goto continue

:help
echo You need three parameters, Top Divisor, Bottom Divisor and ^# of decimal places
echo Example: %0 387 41 20, will divide 387 by 41 out to 20 decimal places. Now you try.
echo Tip: You cannot use a zero "0" for any parameter, all parm's must be positive integers.
goto :EOF

:continue

:: all Variables are self explained 
set /a TopDiv=%1, BotDiv=%2, Precis=(%3-1)/4 + 1, DivRsl=TopDiv / BotDiv
set Solution=%DivRsl%.

for /L %%d in (1,1,%Precis%) do (
   set /A "TopDiv=(TopDiv - DivRsl * BotDiv) * 10000"
   if "!TopDiv!" equ "0" goto Finished
   set /A DivRsl=TopDiv / BotDiv
   set Rsl=0000!DivRsl!
   set Solution=!Solution!!Rsl:~-4!
)
:Finished

echo The solution to %1 / %2 is %Solution%

Code: Select all

@echo off
setlocal EnableDelayedExpansion

rem Divide two integers with unlimited precision result

rem Check parameters
if "%3" equ "" goto help
ver > NUL
set /A TopDiv=%1, BotDiv=%2, Precis=%3  2>NUL
if not errorlevel 1 goto checkBotDiv

:help
echo You need three parameters: Top Divisor, Bottom Divisor and # of decimal places.
echo Example: %0 387 41 20, will divide 387 by 41 out to 20 decimal places.
echo The maximum number (in absolute value) is 2147483647.
goto :EOF

:checkBotDiv
if %BotDiv% neq 0 goto continue

:badNum
echo These numbers can not be divided; change one of them.
if defined Solution echo Partial result: %sign%%Solution%
goto :EOF

:continue
set "sign1=" & set "sign2=" & set "sign="
if "%TopDiv:~0,1%" equ "-" set "sign1=-" & set TopDiv=%TopDiv:~1%
if "%BotDiv:~0,1%" equ "-" set "sign2=-" & set BotDiv=%BotDiv:~1%
if "%sign1%" neq "%sign2%" set "sign=-"
set /A DivRsl=TopDiv / BotDiv, TopDiv-=DivRsl * BotDiv
set "Solution=%DivRsl%."
set "zeros=000000000"

:DivideMe

   if %TopDiv% equ 0 goto Finished
   set digits=0
   for /L %%a in (3,-1,0) do (
       set /A "digits|=1<<%%a"
       for %%b in (!digits!) do if "!TopDiv:~%%b,1!" equ "" set /A "digits&=~1<<%%a"
   )
   set /A digits+=1, wide=9-digits
   if %wide% leq 0 goto badNum
   set /A TopDiv=%TopDiv%!zeros:~%digits%!, DivRsl=TopDiv / BotDiv, TopDiv-=DivRsl * BotDiv, Precis-=wide
   set DivRsl=%zeros%%DivRsl%
   set Solution=%Solution%!DivRsl:~-%wide%!

if %Precis% gtr 0 goto DivideMe

:Finished
echo %sign%%Solution%
goto :EOF