function strcolumn,number,param2,param3,fill

if n_params() le 2 then begin
  if (size(number,/type) ge 4) and (size(number,/type) le 6) then begin
    digits=strsplit(string(number),'.',/extract)
    while strmid(digits[1],0,/reverse_offset) eq '0' do digits[1]=strmid(digits[1],0,strlen(digits[1])-1)
    digits=strlen(digits[1])
  endif else digits=0
  if n_params() eq 1 then length=0 else length=param2
endif else begin
  digits=param2
  length=param3
endelse
if n_params() lt 4 then fill=' '
if size(number,/type) ne 7 then begin
  number=strsplit(strcompress(string(round(number*10^digits)/double(10^digits)),/remove_all),'.',/extract)
  number[1]=strmid(number[1],0,digits)
  if number[1] eq '' then number=number[0] else number=number[0]+'.'+number[1]
endif else number=strtrim(number,2)
if strlen(number) ge length then output=number else begin
  output=''
  for i=0,(length-strlen(number))/strlen(fill) do output=output+fill
  output=strmid(output+number,length-1,/reverse_offset)
endelse
return,output

end