CODEWITHSUNDEEP
windowsbatch-file
ChaBat10
ChaBat10

Reputation: 83

Multiplying Two Whole Numbers In Batch

I am trying to make a Shutdown dialogue in Batch and I have run into a slight problem. I don't like how Windows 8 asks you for the time in seconds when you would like to remote shutdown your own computer with a timer and I am trying to make a batch file that converts a given number (minutes) into seconds.

I have searched the vast majority of the interwebs and cannot find a way to multiply two whole numbers in a batch file.

Here is what I have so far:

@echo off  
echo Enter a number:  
set /p %num1%=  
echo Enter another:  
set /p %num2%=  
set /a sum1=%num1%*%num2%  
echo The total is %sum1%  
pause

Could some kind soul please tell me where I have gone wrong?

Thanks Charlie B

Upvotes: 7

Views: 24290

Answers (4)

user28128515
user28128515

Reputation: 1

I recently wrote a batch version of expr:


    @echo off
    setlocal
    if %1.==. goto help
     echo.
     echo expr: integer math only!
     echo.

     (set /a ans=%*)
     echo ans: %ans%
     exit /b
   :help
     echo expr: command line calculator. v0.01 (2024-Nov-03)
     echo usage: expr {your expression here}

As my code indicates I wasn't able to get my little script to perform the math using real (float) numbers. However, it's good enough to work as a four function integer calculator. When I researched this further, I discovered the only way to calculate floating values in windows was to use powershell or a windows version of bash. I'm actually thinking of recreating expr in C that will properly parse the command line, but this is way down on the priorities list.

Upvotes: 0

BLUEPIXY
BLUEPIXY

Reputation: 40145

fix to

@echo off  
echo Enter a number:
set /p num1=  
echo Enter another:
set /p num2=
set /a sum1="num1 * num2"
echo The total is %sum1%  
pause

Upvotes: 8

Monacraft
Monacraft

Reputation: 6620

This will do what you want:

@echo off
Echo Time to Shutdown:
set /p "min=Time(Min): "
set /a sec=min*60
shutdown /t %sec%

That doesn't handle invalid input, but for your program that won't be a problem. (If you want it to error handle comment so).

Mona

Upvotes: 6

SachaDee
SachaDee

Reputation: 9545

You don't have to put the "%" in the declaration of your variables

@echo off  
echo Enter a number:  
set /p num1=  
echo Enter another:  
set /p num2=  
set /a sum1=%num1%*%num2%  
echo The total is %sum1%  
pause

Upvotes: 2

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