A Function to help with Health Bars ect. in DBPro

This function is a very simple and flexible little addition to any program requiring percentage feedback of some sort or another. All the variables are simple a-b-c-a$-b# and so on. Feel free to use this code whenever and wherever. Its all yours for free. Oh yeah and by the way, the stuff above the function was how it all started so I figured it might come in handy if you run into problems understanding my function. It is also to show the usage of color I added to it.

                                    ` This code was downloaded from The Game Creators
                                    ` It is reproduced here with full permission
                                    ` http://www.thegamecreators.com
                                    
                                    black=rgb(0,0,0)
red=rgb(255,0,0)
yellow=rgb(255,255,0)
white=rgb(255,255,255)
start:
cls
randomize timer()
hp2#=rnd(9998)+1
hp1#=rnd(hp2#)
hpper#=hp1#/hp2#
hpper=percent(hpper#)
hpper$=str$(hpper)+"%"
hp1$=str$(hp1#)
hp2$=str$(hp2#)
hp12$=hp1$+"/"+hp2$
if hpper<25 or hpper=25 then ink yellow,black
if hpper>20 then ink white,black
if hpper<=0 then ink red,black
center text screen width()/2,2,hp12$
center text screen width()/2,15,hpper$
ink white,black
line (screen width()/2)-55,30,(screen width()/2)+55,30
line (screen width()/2)-55,30,(screen width()/2)-55,50
line (screen width()/2)-55,50,(screen width()/2)+55,50
line (screen width()/2)+55,30,(screen width()/2)+55,51
ink red,black
box (screen width()/2)-50,35,((screen width()/2)-50)+hpper,45
suspend for key
if inkey$()="q" then exit
goto start
function percent(a#)
a$=str$(a#)
b$=mid$(a$,1)
b=val(b$)
if b<1
   a=len(a$)
   a$=right$(a$,a-2)
   b$=mid$(a$,1)
   if b$="0"
      b$=mid$(a$,2)
      b=val(b$)
      if b>4 then goto notzero
      b$=mid$(a$,3)
      b=val(b$)
      if b>4 then goto notzero
      perval=0
      goto funcend
   endif
   notzero:
   b$=mid$(a$,3)
   a$=left$(a$,2)
   a=val(a$)
   b=val(b$)
   if b>4
      a=a+1
   endif
   b$=mid$(a$,4)
   b=val(b$)
   if b>4
      a=a+1
   endif
   a$=str$(a)
   perval=val(a$)
   goto funcend
endif
if b>1 or b=1
hund$=str$(b)
   a=len(a$)
   a$=right$(a$,a-2)
   b$=mid$(a$,3)
   a$=left$(a$,2)
   a=val(a$)
   b=val(b$)
   if b>4
      a=a+1
   endif
   b$=mid$(a$,4)
   b=val(b$)
   if b>4
      a=a+1
   endif
   a$=str$(a)
   a$=hund$+a$
   perval=val(a$)
endif
funcend:
endfunction perval