pro humane
; define human understandable quantities and expose them to the
; command line
; this also serves as an example of how to use oJaques g3d method
; get_3D-data. You could do all this also on the command line and
; will have to for large data
@common_blocks.inc

lis = ["Density"]
if (list_str[var_index] ne "Density") then lis = ["Density", list_str[var_index]]

da = oj->g3d(data_fields=["Density", list_str[var_index]])
x = *da.xp
y = *da.yp
z = *da.zp
dx = da.dxl[*da.lp]
vol = dx^3
deni = where(da.data_fields eq "Density")
d    = (*da.dp[deni[0]])
mass = d * vol
vi = where(da.data_fields eq list_str[var_index])
v = (*da.dp[vi[0]])
radius = sqrt((x-center[0])^2+(y-center[1])^2+(z-center[2])^2)
; return log of density and quantity if it makes sense
d = alog10(d)
v = shouldbe_logged(list_str[var_index]) ? alog10(v) : v
print, lis, da.data_fields[0:4]

return
end