"bswap()" worked perfectly! Everything is working now, finally :) For those 
interested, the appended file contains a working vtk export function.
Thanks for the help Tobias!

Am Sonntag, 15. März 2015 13:28:58 UTC+1 schrieb Tobias Knopp:
>
> for l=1:length(x)
>   x[l] = bswap(x[l])
>   y[l] = bswap(y[l])
>   z[l] = bswap(z[l])
> end
>
>
> Am Sonntag, 15. März 2015 11:17:53 UTC+1 schrieb Christian Dengler:
>>
>> Hello again,
>>
>> No that did not do the trick, but i managed to compare the julia output 
>> to a working .vtk file, using a binary reader. The problem with the julia 
>> output, is that it is written LittleEndian, while paraview needs BigEndian. 
>> Also the structure must be write(fid, hcat(x[:]', y[:]', z[:]') ), but 
>> written with BigEndians, which i haven't figured out how to do yet. I tried 
>> the hton() function, as well as NetworkByteOrder from the docs, but i 
>> guess i'm applying it wrong. I tried
>>
>> write(fid, hcat(x[:]', y[:]', z[:]') , NetworkByteOrder) -> NetworkByteOrder 
>> not defined
>> write(fid, hcat(x[:]', y[:]', z[:]') , "NetworkByteOrder") -> writes the 
>> string to the file, instead of changing endianness
>> write(fid, hton(hcat(x[:]', y[:]', z[:]'))) -> ERROR: `bswap` has no 
>> method matching bswap(::Array{Float64,2})
>>
>> Any suggestions how to write big endian?
>>
>>
>> Am Samstag, 14. März 2015 20:05:50 UTC+1 schrieb Tobias Knopp:
>>>
>>> not familiar with the vtk format but are you sure the the x,y,z 
>>> coordinates lay not directly after each other?
>>> Could try:
>>>
>>> write(fid, vcat(x[:]', y[:]', z[:]') )
>>>
>>> Am Samstag, 14. März 2015 18:54:59 UTC+1 schrieb Christian Dengler:
>>>>
>>>> Ty for your answers. I'm not familiar with vtk export on python, and 
>>>> i'm confident that finding my mistake will be easier than trying to 
>>>> understand what you did there with pycall.
>>>> As for the nrrd code, it seems to be doing exactly what i did. I found 
>>>> one mistake i did previously though, telling paraview to load float 
>>>> instead 
>>>> of double values. Now with the function below, paraview loads the files 
>>>> withoud error message, yet doesnt display anything reasonable, seems that 
>>>> there is another mistake somewhere, i still assume it to be the "write" 
>>>> function, where i'm not sure if it does what i want it to.
>>>> I'll keep you up to date, should i find my mistake
>>>>
>>>> function exportVTK(DataMat, NameMat ,filename, dh, Nxyz)
>>>>
>>>> nx = dh[1]*(Nxyz[1]-1);
>>>> ny = dh[2]*(Nxyz[2]-1);
>>>> nz = dh[3]*(Nxyz[3]-1);
>>>>
>>>> x, y, z = ndgrid(0:dh[1]:nx, 0:dh[2]:ny, 0:dh[3]:nz );
>>>>
>>>> nr_of_elements = length(x);
>>>> fid = open(filename, "w"); 
>>>>
>>>> #ASCII file header
>>>> println(fid, "# vtk DataFile Version 3.0");
>>>> println(fid, "VTK from Julia");
>>>> println(fid, "BINARY\n");
>>>> println(fid, "DATASET STRUCTURED_GRID");
>>>> println(fid, "DIMENSIONS $(size(x,1)) $(size(x,2)) $(size(x,3)) ");
>>>> println(fid, "POINTS $(nr_of_elements) double");
>>>> write(fid, [x[:] y[:] z[:]] )
>>>>
>>>> #append data
>>>> print(fid, "\nPOINT_DATA $(nr_of_elements) \n");
>>>>
>>>> for i = 1:length(DataMat)
>>>>
>>>>     if size(DataMat[i], 2) == 3
>>>>     #append a vector
>>>>         println(fid, "\nVECTORS $(NameMat[i]) double"); 
>>>>     elseif size(DataMat[i], 2) == 1
>>>>     #append a scalar
>>>>         println(fid, "\nSCALARS $(NameMat[i]) double");
>>>>         println(fid, "LOOKUP_TABLE default"); 
>>>>     else
>>>>         error("DataMat $i is not a vector or scalar, or not shaped the 
>>>> way it should be")
>>>>     end
>>>>     
>>>>     write(fid, DataMat[i]);
>>>>
>>>> end
>>>>
>>>> close(fid);
>>>>
>>>> end
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> Am Samstag, 14. März 2015 17:49:50 UTC+1 schrieb Kristoffer Carlsson:
>>>>>
>>>>> One method that I have used to export VTK from Julia is simply using 
>>>>> the VTK-library from python and calling it with PyCall.
>>>>>
>>>>> Something like this: 
>>>>> https://gist.github.com/KristofferC/9a989a2c0518bb70009c
>>>>>
>>>>>
>>>>>
>>>>> On Saturday, March 14, 2015 at 1:41:04 PM UTC+1, Christian Dengler 
>>>>> wrote:
>>>>>>
>>>>>> Hello,
>>>>>>
>>>>>> I'm trying to save my data as .vtk files, and ran into a problem with 
>>>>>> the "print" and "write" function.
>>>>>>
>>>>>> Resumee of what would solve my problems:
>>>>>> - Using print(filestream, data), but omitting the square brackets, and
>>>>>> - using print(filestream, vector), and actually writes the vector, 
>>>>>> one element per line
>>>>>>
>>>>>> Does anyone know how this is done?
>>>>>>
>>>>>> Another way of creating .vtk files using binary data, using the write 
>>>>>> function, didn't lead to any success, but i cant really say whats wrong, 
>>>>>> because the files are unreadable. Could it be, that write also somehow 
>>>>>> includes brackets?
>>>>>>
>>>>>>
>>>>>> For those who want to see my problem in code, i attached a script, 
>>>>>> creating and saving a simple veocity field as .vtk (ASCII) file.
>>>>>> After manually deleting the brackets, atleast the velocity can be 
>>>>>> imported into paraview.
>>>>>> In order to create the binary .vtk file (thats not working at all), i 
>>>>>> used to replace "ASCII" by "BINARY", and "print" in line 22 and  41 by 
>>>>>> "write".
>>>>>>
>>>>>> Greetings, 
>>>>>> Christian
>>>>>>
>>>>>

Attachment: vtkexample.jl
Description: Binary data

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