Question

[Magdy Sanad]

  Dear Dr.      
          
          I'm a Researcher  from Cairo, Egypt.
          
    I installed the language programmer  (Python)  on my PC.  I executed  the following statements to read unformatted fortran data. I have the  original program which I translate it to the Python language :
    
  pro rd_gadget, f=fname, d = data, h=   hdr, swap=swap
      

;modified from Volker's read_snapshot_single.pro to be a free-standing
;program that reads fname, and returns data and header structures M-MML 
6/16/06

;added option to swap byte order to read Intel files on PowerPC
;11/8/06 M-MML


    if not keyword_set(fname) then 
fname="/home/vspringe/ICs/galaxy.dat.intel"
    
    npart=lonarr(6) 
    massarr=dblarr(6)
    time=0.0D
    redshift=0.0D
    flag_sfr=0L
    flag_feedback=0L
    npartTotal=lonarr(6) 
    bytesleft=256-6*4 - 6*8 - 8 - 8 - 2*4-6*4
    la=intarr(bytesleft/2)

    openr,1,fname,/f77_unformatted, swap_endian = swap

    
readu,1,npart,massarr,time,redshift,flag_sfr,flag_feedback,npartTotal,la

    hdr = { np: npart, mass: massarr, time: time, z: redshift, sfr: $
                 flag_sfr, fb: flag_feedback, nptot: npartTotal, la: 
la}

    N=total(npart)
    pos=fltarr(3,N)
   
 vel=fltarr(3,N)
    id=lonarr(N)
 
    ind=where((npart gt 0) and (massarr eq 0)) 
    if ind(0) ne -1 then begin
 Nwithmass= total(npart(ind))
        mass=fltarr(Nwithmass)
    endif else begin 
        Nwithmass= 0
    endelse

    nfield = 0

    readu,1,pos
    nm = 'position'
    nfield = nfield + 1

    readu,1,vel
    nm = [nm, 'velocity']
    nfield = nfield + 1

    readu,1,id
    nm = [nm, 'id']
    nfield = nfield + 1


    if Nwithmass gt 0 then begin
      readu,1,mass
      nm = [nm, 'mass']
      nfield = nfield + 1
    endif

    NGas=npart(0)

    if Ngas gt 0 then begin

        u=fltarr(Ngas)
        readu,1,u
        nm = [nm, 'gas specific energy']
        nfield = nfield + 1

        rho=fltarr(Ngas)
        readu,1,rho
        nm = [nm, 'gas density']
        nfield = nfield + 1
   endif
   close,1


  
 if (nfield lt 3) or (nfield gt 6) then $
    print,'RD_GADGET: Unexpected number of data fields, nfield = 
',nfield $
   else if nfield eq 3 then $
    data = { nf: nfield, nm: nm, pos: pos, vel: vel, id: id } $
   else if nfield eq 4 then $
    data = { nf: nfield, nm: nm, pos: pos, vel: vel, id: id, mass: mass 
} $
   else if nfield eq 6 then $
    data = { nf: nfield, nm: nm, pos: pos, vel: vel, id: id, mass: 
mass, $
             spe: u, den: rho }

end
    Below you will find my attempt to translate the first part of this program  to Python  language 
    
    import scipy.io.mio
    import Numeric
    from Numeric import *
    file_hdg = 'D:/mm/hdg'
    # Integer (Long) Arrays
    npart = array (6)
    # Floating point (double precision) array
    massarr = array(6)
    time=0.0
    redshift=0.0
    flag_sfr=0L
    flag_feedback=0L
    npartTotal=array(6)
    bytesleft=256-6*4 - 6*8 - 8 - 8 -   2*4-6*4
    la=array(bytesleft/2)
    def readdata ( filePath ):
        fileHandle = scipy.io.mio.fopen( filePath, 'r')
    def fort_read(self,fmt,dtype=None):
        numberOfBlocks = fileHandle.fort_read( 1 , 'l' )
        print numberOfBlocks
    readdata (file_hdg),npart,massarr,time,redshift,flag_sfr,flag_feedback,npartTotal,la
     
    All these commands are accepted, the result with the last command :
      
readdata(file_hdg),npart,massarr,time,redshift,flag_sfr,flag_feedback,npartTotal,la
 
Is
 
(None, 6, 6, 0.0, 0.0, 0L, 0L, 6, 68)
    I will be very appreciated if you send me your opinion  about this and what the 
    
     ( None ) means in this result.  
            
    Best   Regards
          
          Magdy Sanad
          
          National Research Institute of
          Astronomy and Geophysics
            Astronomy Department
          Helwan - Cairo - Egypt
 	 
---------------------------------
Looking for earth-friendly autos? 
 Browse Top Cars by "Green Rating" at Yahoo! Autos' Green Center.  
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20070212/b7c9f637/attachment.html>