Classes

vi

To calculate the vegetation indices. This class contain the following functions:

	get_vi => To get the Vegetation Indices. 
                  The followign indices can be calculated : 
								RVI
								NDVI
								IPVI
								DVI
								RNDVI
								MRVI
								MPRI
								SAVI
								EVI2
								MGNDVI
								MNDVI
								BI
								RGRI 
								GNDVI 
								NDRGI   
								NDVSI   
								RDI  
								TNDVI
								GRVI  
								OSAVI  
								MGRVI
								SLAVI
								NDMI