In my project I use 8 sources and 1 detector and now I need to convert raw data (.CSV) to .NIRS, but I have no .POS file? 

Would you please tell me how to create this file and in which environment ?

Can I use your .POS file (ex. 3*5 ) for my project or it is necessary for me to create my own .POS file?   

I am new in this field, so I will be appreciated it if you could answer my question.


Thanks.

if you have 8 sources and 1 detector, then you will likely be better off modifying the 2x3x3 file to have your detector as ch5 and your sources as ch1-4 and ch 6-9, and removing the remaining ch10-18. Remember that this will have no meaning anatomically and is only for a quick way of displaying your data.

Best of luck,

Rebecca

Ok, I will do that thanks a lot. 

Another question is that, I have run the code for my .CSV file, but it takes a long time. I do not know why ? I could not get my .nirs result yet. 

The number of row in my .CSV file is 31911.

You will also need to edit the matlab script you are using to enable it to handle 8 channel data as it is currently written only to handle 24 channels in the three standard configurations provided using the Hitachi ETG4000. As it is currently written, the script will error and fail to run using 8 channel data, even with an appropriate pos file.

Rebecca

Originally posted by Rebecca Dewey:
Ok, Thank you so much. 
I will do that.  

If I use two optode arrays,one is 3*5, another is 4*4,how should I choose the .POS file?

Hello, you will need to create one pos file with all the optode locations in. The most genuine way to do this is by using a localiser to create one based on the real-life locations of the optodes. However, if you just want to conveniently visualise the data, you can easily start experimenting with the most helpful orientation for this by copying and pasting the locations from one pos file into the other, updating the optode numbers in sequence, and off-setting all the optodes in one array by a fixed amount in one dimension (e.g., adding 12 cm to the x dimension for all the optodes in the 4x4 array while leaving the 3x5 array as it is.

Good luck!