Re: read + unpack

Your data doesn't look like binary, looks like text. If your data is really binary, please provide a short hexdump we can use to test your code, like this

C:\>hexdump datafile | head
00000000: 45 43 48 4F 20 69 73 20 - 6F 6E 2E 0D 0A          |ECHO is o
+n.  |
0000000d;

C:\>od -tx1 datafile | head
0000000 45 43 48 4f 20 69 73 20 6f 6e 2e 0d 0a
0000015

C:\>
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Comment on Re: read + unpack Download Code

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Re^2: read + unpack by andri85 (Novice) on May 06, 2009 at 22:42 UTC
The data should be binary, indeed with matlab I'm not reading it as a text and it works fine. Another hint, a friend of mine wrote a c++ code that outputs the correct numbers and it works: // Read the pink photon data arg_file.read(num_photons_bin, 1); pink_photons = (unsigned int) num_photons_bin; // Increment the counter based on the bytes read status_counter += 1; // Read pink photon data for (int photon = 0; photon < pink_photons; photon++) { // Read the binary data into the variable arg_file.read((char )&pink_x_pos, sizeof(double)); arg_file.read((char )&pink_y_pos, sizeof(double)); arg_file.read((char )&pink_z_pos, sizeof(double)); arg_file.read((char )&pink_num_scatters, sizeof(int)) +; arg_file.read((char )&pink_col_scatters, sizeof(int)) +; arg_file.read((char *)&pink_energy_val, sizeof(double) +); } [download] So to my understanding this is a bin file. Regarding the hexdump, unfortunately the file has a 32768bytes header so I don't know how to skip them for the hexdump (what do I have to put instead of "head"?). Thank you very much for your attention. Andri	[reply] [d/l]

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Re^2: read + unpack
by andri85 (Novice) on May 06, 2009 at 22:42 UTC

// Read the pink photon data
            arg_file.read(num_photons_bin, 1);
            pink_photons = (unsigned int) *num_photons_bin;
            
            // Increment the counter based on the bytes read
            status_counter += 1;
            
            // Read pink photon data
            for (int photon = 0; photon < pink_photons; photon++)    {
                // Read the binary data into the variable
                
                arg_file.read((char *)&pink_x_pos, sizeof(double));
                arg_file.read((char *)&pink_y_pos, sizeof(double));
                arg_file.read((char *)&pink_z_pos, sizeof(double));
                arg_file.read((char *)&pink_num_scatters, sizeof(int))
+;
                arg_file.read((char *)&pink_col_scatters, sizeof(int))
+;
                arg_file.read((char *)&pink_energy_val, sizeof(double)
+);
}
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