I need to do a floating-point division in a dos batch.
I didn't find a way to do it. Something like this :
SET /A Res=10/3
returns a integer number.
Is it possible to do it ?
Use double percent signs ( %% ) to carry out the for command within a batch file. Variables are case sensitive, and they must be represented with an alphabetical value such as %a, %b, or %c. ( <set> ) Required. Specifies one or more files, directories, or text strings, or a range of values on which to run the command.
A floating point division where a number divides another number can be expressed as. Thus it can be said that in a floating point division, mantissas are divided and exponents are subtracted. The major steps for a floating point division are. Extract the sign of the result from the two sign bits.
The tilde (~) sign is used in different ways in batch files: Argument quote removal. A tilde sign before an command-line argument (such as "%~1") indicates to remove the surrounding quotes from the parameter. Such if the value for %1 is "Hi" then %~1 will expand to only Hi.
I know this is a very old topic, but I can't found a simple Batch method in all previous answers, so I post here a pure Batch solution that is very simple to use.
Perform operations using fixed point arithmetic in Batch is simple. "Fixed point" means that you must set a number of decimals in advance and keep it throughout the operations. Add and subtract operations between two Fixed Point numbers are performed directly. Multiply and division operations requires an auxiliary variable, that we can call "one", with the value of 1 with the right number of decimals (as "0" digits). After multiply, divide the product by "one"; before division, multiply the dividend by "one". Here it is:
@echo off
setlocal EnableDelayedExpansion
set decimals=2
set /A one=1, decimalsP1=decimals+1
for /L %%i in (1,1,%decimals%) do set "one=!one!0"
:getNumber
set /P "numA=Enter a number with %decimals% decimals: "
if "!numA:~-%decimalsP1%,1!" equ "." goto numOK
echo The number must have a point and %decimals% decimals
goto getNumber
:numOK
set numB=2.54
set "fpA=%numA:.=%"
set "fpB=%numB:.=%"
set /A add=fpA+fpB, sub=fpA-fpB, mul=fpA*fpB/one, div=fpA*one/fpB
echo %numA% + %numB% = !add:~0,-%decimals%!.!add:~-%decimals%!
echo %numA% - %numB% = !sub:~0,-%decimals%!.!sub:~-%decimals%!
echo %numA% * %numB% = !mul:~0,-%decimals%!.!mul:~-%decimals%!
echo %numA% / %numB% = !div:~0,-%decimals%!.!div:~-%decimals%!
For example:
Enter a number with 2 decimals: 3.76
3.76 + 2.54 = 6.30
3.76 - 2.54 = 1.22
3.76 * 2.54 = 9.55
3.76 / 2.54 = 1.48
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