Error with If-Else statement combine with Math in .bat file - math

Question

It's supose to be simples, but i can't get it working ! Maybe someone could help...
I just need a program that check if '07503.csv' file exists, and than '07504.csv', '07505.csv'...until '07552.csv'. Here i'm supose to end the program (it's simplified so you can understand my problem).
This works:
SET angle=075
SET velocity=03
SET finalfilename=.csv
SET endofsequency=07552
SETLOCAL EnableDelayedExpansion
:loop
SET currentsequency=%angle%%velocity%
SET fullfilename=%currentsequency%%finalfilename%
:CHECK_FILES
IF EXIST %fullfilename% (
ECHO FILE FOUND: %fullfilename%
GOTO :GO_TROUGHT
) ELSE (
ECHO FILE NOT FOUND: %fullfilename%
GOTO :WRITE_LOG
)
:WRITE_LOG
ECHO %time% missing: %fullfilename%
ECHO %time% missing: %fullfilename% >> FilesMissed.txt
:GO_TROUGHT
FOR /F "tokens=* delims=0" %%A IN ("%velocity%") DO SET velocity=%%A
SET /A velocity+=1
SET velocity=000%velocity%
SET velocity=%velocity:~-2%
PAUSE
IF %currentsequency% NEQ %endofsequency% GOTO loop
:END
PAUSE
But with IF-ElSE statement does not:
SET angle=075
SET velocity=03
SET finalfilename=.csv
SETLOCAL EnableDelayedExpansion
:loop
SET currentsequency=%angle%%velocity%
SET fullfilename=%currentsequency%%finalfilename%
:CHECK_FILES
IF EXIST %fullfilename% (
ECHO FILE FOUND: %fullfilename%
GOTO :GO_TROUGHT
) ELSE (
ECHO FILE NOT FOUND: %fullfilename%
GOTO :WRITE_LOG
)
:WRITE_LOG
ECHO %time% missing: %fullfilename%
ECHO %time% missing: %fullfilename% >> FilesMissed.txt
:GO_TROUGHT
IF "%velocity%" NEQ "52" (
FOR /F "tokens=* delims=0" %%A IN ("%velocity%") DO SET velocity=%%A
SET /A velocity+=1
SET velocity=000%velocity%
SET velocity=%velocity:~-2%
) ELSE (
GOTO :END
)
PAUSE
GOTO :loop
:END
PAUSE
My question is why? What's happening? Can't i use FOR inside a IF-ELSE ? Idk ...
Regards,

Answer 1

Without reading closely - will using this help instead?
IF "%velocity%" EQU "52" goto :END
Looking a bit closer - it is an issue with delayed expansion. You need to enable it and then use !variable! instead of %variable% when inside parenthesis.
EDIT: try this with delayed expansion. The first line is changed, and the two last SET velocity= lines are changed.
setlocal enabledelayedexpansion
SET angle=075
SET velocity=03
SET finalfilename=.csv
SETLOCAL EnableDelayedExpansion
:loop
SET currentsequency=%angle%%velocity%
SET fullfilename=%currentsequency%%finalfilename%
:CHECK_FILES
IF EXIST %fullfilename% (
ECHO FILE FOUND: %fullfilename%
GOTO :GO_TROUGHT
) ELSE (
ECHO FILE NOT FOUND: %fullfilename%
GOTO :WRITE_LOG
)
:WRITE_LOG
ECHO %time% missing: %fullfilename%
ECHO %time% missing: %fullfilename% >> FilesMissed.txt
:GO_TROUGHT
IF "%velocity%" NEQ "52" (
FOR /F "tokens=* delims=0" %%A IN ("%velocity%") DO SET velocity=%%A
SET /A velocity+=1
SET velocity=000!velocity!
SET velocity=!velocity:~-2!
) ELSE (
GOTO :END
)
PAUSE
GOTO :loop
:END
PAUSE

Answer 2

This is the way I would do that:
#ECHO OFF
SETLOCAL EnableDelayedExpansion
SET angle=075
SET "velocity=103" // Will use just 2 last digits of velocity
SET finalfilename=.csv
SET "endVelocity=152" // The same here...
SET /A numberOfValues=endVelocity - velocity + 1
for /L %%i in (1,1,%numberOfValues%) do (
SET fullfilename=%angle%!velocity:~-2!%finalfilename%
rem CHECK_FILES
IF EXIST !fullfilename! (
ECHO FILE FOUND: !fullfilename!
) ELSE (
ECHO FILE NOT FOUND: !fullfilename!
rem WRITE_LOG
ECHO !time! missing: !fullfilename!
ECHO !time! missing: !fullfilename! >> FilesMissed.txt
)
SET /A velocity+=1
PAUSE
)
PAUSE

Answer 3

Like #Aacini's answer, the following uses a FOR /L loop, but the method is slightly different:
#ECHO OFF
SET angle=075
SET startvelocity=3
SET endvelocity=52
SET ext=.csv
SET /A startnum=1%angle%*100+startvelocity
SET /A endnum=1%angle%*100+endvelocity
FOR /L %%i IN (%startnum%,1,%endnum%) DO (
SET "filename=%%i%ext%"
SETLOCAL EnableDelayedExpansion
IF EXIST !filename:~1! (
ECHO FILE FOUND: !filename:~1!
) ELSE (
ECHO FILE NOT FOUND: !filename:~1!
SET "logline=!time! missing: !filename:~1!"
ECHO !logline!
ECHO !logline!>> FilesMissed.txt
)
ENDLOCAL
)
That is, the loop is iterating over values like
107503
107504
107505
...
The leading 1 was added to preserve the 0 before the 75. (Leading 0s are lost in arithmetical operations.)
In the loop body, the value of the loop variable is used to construct a file name:
107503.csv
107504.csv
...
The leading 1 is later dropped (using ~1 when expanding the name).
Additionally, in case what you are writing to the FilesMissed.txt file is always meant to be duplicated on the screen, I introduced a variable to show how you could make sure the contents is duplicated exactly, allowing you to make changes to the formatting of the line only once. (Could be especially useful if you intended to additionally write the same line to other files.)