Re: STANDARD DEVIATON

[Struan Gray <struan.gray(at)sljus.lu.se>]

Oops.  I need more (or less) coffee:

>function imageSD, image
>   
>   localmean = smooth(float(image), 3, /edge_truncate)
>   localsd = sqrt((float(image)-temporary(localmean))^^2)
>   localsd = smooth(temporary(localsd), 3, /edge_truncate)
>   
>   return, localsd
>
>end

    Naturally, you should take the local average *before*
the square root.
    
    
    function imageSD, image
   
      localmean = smooth(float(image), 3, /edge_truncate)
      localsd = (float(image)-temporary(localmean))^^2
      localsd = smooth(temporary(localsd), 3, /edge_truncate)
      localsd = sqrt(temporary(localsd))
   
      return, localsd

    end
    
    
Struan