[Numpy-discussion] Read array from file

[Lisandro Dalcin]

If you just want to manage VTK files, the you have to definitely try
pyvtk. http://cens.ioc.ee/projects/pyvtk/

I have a similar numpy-based but independent implementation, not fully
tested, targeted to only write VTK files for big datasets (let say,
more than 1 millon nodes) in eider ascii or bynary format. Never found
time for implementing reading.


On 3/14/08, Dimitrios Kiousis <dkiousis@gmail.com> wrote:
> Hello python users,
>
> I have an input file consisting of string-lines and float-lines. This is how
> it looks:
>
> # vtk DataFile Version 3.0
> VTK file exported from FEAP
> ASCII
> DATASET UNSTRUCTURED_GRID
>  POINTS    6935  FLOAT
>   15.44261   12.05814   54.43124
>   15.54899   12.00075   53.85503
>   15.95802   11.92959   53.88939
>   15.84085   12.00235   54.43274
>   15.53889   11.16645   54.51649
>   15.57673   11.10806   53.96009
>    16.10059   11.06809   53.87672
>   16.04238   11.11615   54.47454
>   15.78142   11.82206   53.33932
>   16.13055   11.75515   53.37313
>   .................
>
> I want to read the first 5 string lines, and then store the float data
> (coordinates) into an array.
>  It took me some time to figure this out but this is the script with which I
> came out:
>
>  # Read and write the first information lines
> for i in range(0,5):
>   Fdif.write( Fpst.readline() )
>
> # Read and write coordinates
>  # --------------------------
>
> # Initialization
> coords = zeros( (nnod,3), float )
>
> for i in range(0,nnod):
>   # Read line
>   x = Fref.readline() # Read lines
>   x = x.split()       # Split line to strings
>    x = map ( float,x ) # Convert string elements to floats
>   x = array ( x )     # Make an array
>   for j in range (0,3):
>     coords[i,j] = x[j]
>
> It seems quite complicated to me, but I haven't figure any nicer way. Could
> you tell me if what I am doing looks reasonanble or if there are any other
> solutions?
>  Do I really need to initiallize coords?
>
> Thanks in advance,
> Dimitrios
>
> _______________________________________________
>  Numpy-discussion mailing list
>  Numpy-discussion@scipy.org
> http://projects.scipy.org/mailman/listinfo/numpy-discussion
>
>


-- 
Lisandro Dalcín
---------------
Centro Internacional de Métodos Computacionales en Ingeniería (CIMEC)
Instituto de Desarrollo Tecnológico para la Industria Química (INTEC)
Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)
PTLC - Güemes 3450, (3000) Santa Fe, Argentina
Tel/Fax: +54-(0)342-451.1594