View Single Post
  #9   Report Post  
Posted to microsoft.public.excel.worksheet.functions
Barb Reinhardt Barb Reinhardt is offline
external usenet poster
 
Posts: 3,355
Default Shannon diversity index formula

Try this then:

=-SUMPRODUCT((C$2:C$20/SUM(C$2:C$20)),(IF(C$2:C$200,(LOG(C$2:C$20/SUM(C$2:C$20))))))
Activate with CTRL SHIFT ENTER
You should see {} around the formula when you are done.

"peter" wrote:

This function still evaluates to a #NUM error.

On Apr 8, 2:22 pm, Barb Reinhardt
wrote:
Try this

=-SUMPRODUCT(--(C2:C200),(C2:C20/SUM(C2:C20)),(LOG(C2:C20/SUM(C2:C20))))