function kroupa_imf_shape, mass
; with a list of masses return a N(M)dlog M distribution given by
; Kroupa. I.e. 0.7 below 0.08 then -0.3 and -1.3 power laws above 0.5
; solar masses 
; Assumes input is in solar masses

nmass = N_elements(mass)
imf = fltarr(nmass)
for i=0, nmass-1 do $
   if mass[i] lt 0.08 then imf[i] = 25.*mass[i]^0.7 else $
      if mass[i] lt 0.5 then imf[i] = 2.*mass[i]^(-0.3) else $
         imf[i] = mass[i]^(-1.3) 

return, imf
end