Multiple Variables - Generator

Question

I'm trying to create a 1 line code where it adds up all variables its hard to explain in text right but here's a small part of the code

H = hours
M = Minutes
Thr = Total Hours
Tmin= Total Minutes

Call data.bat 
Rem data.bat is all the h1,m1,h2,m2,h3,m3... info

Rem Example Data
H1=3
M1=53
H2=4
M2=20
Set num=1
:refresh
if %H%num%% GTR 0 set /a Thr=%H%num%%+%Thr%
if %M%num%% GTR 0 set /a Thr=%M%num%%+%TMin%
if %M%num%% EQU 0 Goto :total
set /a number=%number%+1
goto :refresh
:Total
set /a Total=((%Thr%*60)+%Tmin%)
set /a TotalHour=(%Total%/60)
set /a TotalMin=(-%TotalHour%*60)+%Total%
if %Totalmin% GEQ 0 if %Totalmin% LEQ 9 set Totalmin=0%Totalmin%
Echo Duration    : %TotalHour%hr %TotalMin%min

Hours does not have if 0 goto total because there may be times where there was 0 hours but ##'s minutes Any Ideas on how to do this? Running it as is gives me

step by step operation

if %h%num%% gtr 0 set /a Thr=%h%num%%+%thr%
If %h1% gtr 0 set /a thr=%h1%+%thr%
If 3 gtr 0 set /a thr=**3+%thr%
if 3 gtr 0 set /a thr=3+1

Answer 1

you Need delayed Expansion:

setlocal enabledelayedexpansion
set h1=3
set x=1
echo !h%x%!

EDIT to Show how it works with the example in your comment:

setlocal enabledelayedexpansion
set Thr=2
set H3=4
set Num=3
    REM echo if !H%Num%! GTR 0 set /a Thr=!H%num%!+%Thr%
    echo if !H%Num%! GTR 0 set /a Thr+=!H%num%!
    REM if !H%Num%! GTR 0 set /a Thr=!H%num%!+%Thr%
if !H%Num%! GTR 0 set /a Thr+=!H%num%!
echo %Thr%

(note: the intended lines are redundant, just to display, what happens) I used a different syntax to add a value to a variable; Commented out your syntax. Both versions are working the same.

%h%num%% 

will be interpreted as (inserted underscores to Show, how the Parser groups it):

%h%_num_%% 

with %h%(probably) undefined (shown below as ~), %% interpreded as an escaped single literal %, resulting in:

~_num_% 

or without the placeholders:

num%

The same with delayed Expansion:

!H%Num%!

%num%being 3:

!H3!

which is getting expanded to:

4

User jeb wrote a great answer to How does the Windows Command Interpreter (CMD.EXE) parse scripts? (hard stuff, but helps to understand, what's going on)

Answer 2

There are several points in your code that needs to be adjusted:

• The rigth way to access array elements via an index is using Delayed Expansion, as fully explained at Arrays, linked lists and other data structures in cmd.exe (batch) script:

.

if !H%num%! GTR 0 set /a Thr=!H%num%!+%Thr%

• However, the set /a command can directly access array elements when just the name of the variable is given, so in this case it is not necesssary to expand the value:

.

set /a Thr=H%num%+Thr
set /a number=number+1

The last line may also be written this way:

set /a number+=1

• If you want to check if a variable does not exist (and not confuse it with a variable with zero value), you may use if defined command:

.

if defined H%num% goto refresh

• You used the wrong variable name a couple of times: number instead of num, and Thr in the minutes calculation.

.

This is the final code after completed previous modifications:

@echo off

REM H = hours
REM M = Minutes
REM Thr = Total Hours
REM Tmin= Total Minutes

REM Call data.bat 
Rem data.bat is all the h1,m1,h2,m2,h3,m3... info

Rem Example Data
set H1=3
set M1=53
set H2=4
set M2=20
Set num=1
:refresh
set /a Thr=H%num%+Thr
set /a Tmin=M%num%+Tmin
set /a num=num+1
if defined M%num% Goto :refresh
:Total
set /a Total=((Thr*60)+Tmin)
set /a TotalHour=(Total/60)
set /a TotalMin=(-TotalHour*60)+Total
if %Totalmin% LEQ 9 set Totalmin=0%Totalmin%
Echo Duration    : %TotalHour%hr %TotalMin%min

Output:

Duration    : 8hr 13min

Answer 3

If you are looking a formula to parse time and calculate duration, you might look this: Calculate Time difference in Windows batch file