///Los parámetros p y m deben de ser optimizables.
//Parámetros por defecto:
//p=20
//m=1

ivn=NegativeVolumeIndex(close)

np=average[p,m](ivn)

in=(ivn-np)*100/ivn

ivp=PositiveVolumeIndex(close)

vp=average[p,m](ivp)

ip=(ivp-vp)*100/ivp

return ip COLOURED(102,255,102) as "verde"  ,in COLOURED(0,255,255) as "azul",0 as "0"