China DOS Union

Hehe, it's not explanations, it's just that Chinese labels were used. With Chinese labels, even explanations can be omitted!

Originally posted by qwe1234567 at 2006-10-23 03:55:
Hehe, it's not explanations, it's just that Chinese labels were used. With Chinese labels, even explanations can be omitted!

Chinese works too, huh. Haven't tried it yet, not sure how many Chinese characters are supported at most

This is also my first time using Chinese labels. I think there probably isn't a limit on the number

Also, variables can be Chinese too

Originally posted by qwe1234567 at 2006-10-23 04:18:
This is also my first time using Chinese labels. I think there probably isn't a limit on the number

Letters are 8, so I think there should be one. Test it and see

Turns out there really is no limit, hehe~ I'll use Chinese for labels from now on

I tried it. In CMD, letters aren't limited to just 8 either (I guess there isn't much of a limit, or maybe it's 255). You can test it with the following code
@echo off
:abcdefghi
set /p a=Please enter:
if %a%.==5. (goto abcdefghi) else goto abcdefghi1
:abcdefghi1
echo %a%
pause

Originally posted by namejm at 2006-10-4 21:08:
　So far, everyone has already found two methods for calculating floating-point numbers under CMD:

　　Method 1: Calculate the integer part and the fractional part separately. The process is: the integer parts can just be added directly; the fractional part is a bit more troublesome: if the numbers of digits after the decimal point are not the same, then use the one with the most digits as the standard, pad zeros onto the fractional part of the other number, and then perform integer addition on the fractional parts; if the number of digits in the sum exceeds the longest original fractional length, then carry 1 to the integer part, and the highest digit of the fractional part must be reduced by 1 accordingly;

　　Method 2: Recombine the integer part and fractional part into a new number, then perform addition on the new number, and finally insert the decimal point back into its original position;

　　The respective advantages and disadvantages of the two methods:

　　Method 1: Advantage: the range of floating-point numbers it can handle is very large; as long as the result of the addition is between (2^32-1.2^32-1) and -(2^32-1.2^32-1), it can handle it; disadvantage: most problems appear in the fractional part, for example, if the highest digit of the fractional part is 08 or 09, errors may occur, and these two cases need separate handling; if the digit length of the fractional sum exceeds the longest original length, then the integer part must be incremented by 1 and the highest fractional digit must be decremented by 1; if this is extended to addition of three or more floating-point numbers, the carry problem becomes even more complicated;

　　Method 2: Advantage: there is no need to separately handle the 08 and 09 cases, and no need to consider carry problems (after reading pengfei's analysis below, I found that this description is a bit problematic; for details please refer to the explanation below); disadvantage: the range of floating-point numbers it can handle is relatively small; it only succeeds when the range of the new value formed by removing the decimal point from the sum is between (2^32-1.2^32-1) and -(2^32-1.2^32-1).

Excellent!!!!

Most decimals used in daily life are "amounts of money", with only 2 decimal places, so "Method 2" is better!

This thread gave me a lot of inspiration, thanks everyone!!!



[ Last edited by xycoordinate on 2007-3-4 at 10:51 AM ]

If this could be changed into a command-line version (when using it, enter the filename and the corresponding parameters), that would be great.

Labels can also use Chinese, learned something!

@echo off set aa=%1 set bb=%2 ::Call floating-point multiplication function call :mul cc aa bb %3 echo %cc% goto :eof :mul ::Floating-point multiplication function, leading and trailing zeros are allowed, supports products of: 49 integer digits, 49 fractional digits. ::The first parameter is the receiving variable name, the second and third are the names of the multiplicand variables, the fourth specifies how many decimal places to keep @echo off&setlocal enabledelayedexpansion set cc=0 set ka=!%2:*.=! set kb=!%3:*.=! set maa=!%2:.=! set mb=!%3:.=! for /l %%a in (0,1,49) do if not "!maa:~%%a,1!"=="0" (set maa=!maa:~%%a!&goto :maaok) :maaok for /l %%a in (0,1,49) do if not "!mb:~%%a,1!"=="0" (set mb=!mb:~%%a!&goto :mbok) :mbok if "!kb!."=="!%3!." set kb= if "!ka!."=="!%2!." set ka= set kab=!kb!!ka!# for /l %%a in (0,1,49) do if "!kab:~%%a,1!"=="#" (set kab=%%a&goto :lp1) :lp1 if defined mb (set al=!mb:~-4! if "!al:~0,1!"=="0" set/a al=1!al!-10000 set mb=!mb:~0,-4! ) else (goto :endmul) set ma=!maa! set zero=!mz! set mz=!mz!0000 for /l %%a in (1,1,12) do ( if defined ma (set bl=!ma:~-4! if "!bl:~0,1!"=="0" set/a bl=1!bl!-10000 set/a bl*=al&set ma=!ma:~0,-4! ) else (goto :end1) set bl=!bl!!zero! set zero=!zero!0000 call :add cc cc bl ) :end1 goto :lp1 :endmul if not %kab%==0 ( set ka=00000000000000000000000000000000000000000000000000%cc% if "!cc:~0,-%kab%!"=="" (set cc=0.!ka:~-%kab%,%4!) else (set cc=!cc:~0,-%kab%!.!cc:~-%kab%,%4!) ) endlocal&set %1=%cc%&goto :eof :add set xa=%cc% set xb=%bl% set cc= set zz=0 set zy= for /l %%a in (9,9,81) do ( if "!xa!!xb!"=="" goto :end set cc=!zy!!cc! if defined xa (set "aa=000000000!xa:~-9!"&set xa=!xa:~0,-9!) else (set aa=000000000) if defined xb (set "bb=000000000!xb:~-9!"&set xb=!xb:~0,-9!) else (set bb=000000000) set/a zz=!zz:~0,-9!+1!bb:~-9!-1000000000+1!aa:~-9!-1000000000 set zy=000000000!zz! set zy=!zy:~-9! ) :end set cc=%zz%%cc% if not %cc% gtr 0 goto :endok if "%cc:~0,2%"=="0." goto :endok for /l %%a in (0,1,36) do if not "!cc:~%%a,1!"=="0" (set cc=!cc:~%%a!&goto :endok) :endok goto :eof

[ Last edited by netbenton on 2009-4-5 at 10:30 ]

The one on the 4th floor is like a heavenly book...
But why go so deep into floating-point operations? I haven't seen many batch files that actually need floating-point calculations. You experts really are too bored.

What does this line mean??
if "%number1:~0,1%"=="." set number1=0%number1%

What does this line mean??
if "%number1:~0,1%"=="." set number1=0%number1%