Binary file write cancatenat​ion during writing

Hi, 
I'm trying to write a 2D array into a binary file and save the whole complete array in 2D.  As shown in the picture, data is written and appended to the binary file during each loop.  However, each loop would generate a 5x800 2D array (5 rows, 800 elements in each row).  Right now I have to use another vi to process the binary file I saved to concatenate all the arrays in the binary file to finally obtaion a 5 x 800n (n is the number of loops) array.  Is there a way to save the data into binary file in that format during each loop instead of writing into different segments and I have to concatenate different segments together after that?  
On the other hand, if there's a way to do that, would that increase the loop cycle time because it's more computationally expensive?  Thank you very much for your help.
Thank you,
Charles
Attachments:
picture2.png ‏37 KB

See the attached examples.
If you have the file open you can basically just write data to it whenever you have it available, just do not include the length. It can cost a bit to write single elements so the row option is more commonly used, but it depends on how large each row is (if they are huge then it will cost to much to keep them in memory and you write parts of each row instead...). 
I have not covered cases where you need to close the file and add data later, but the difference then is just that you need to set the write position after you have re-opened the file.
MTO
Attachments:
Write and read 2D array.vi ‏26 KB

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    UTL_FILE - http://download-uk.oracle.com/docs/cd/B19306_01/appdev.102/b14258/u_file.htm#sthref14095
    http://psoug.org/reference/dbms_lob.html
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    writefile.vi ‏27 KB
    openfile.vi ‏26 KB

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    writefile.vi ‏38 KB

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