cell of box domain from cell ID to the I,j,k

I’m now able to find the ID of the cell containing a set of data (representing a polymer molecule) but since I’m using a cubic 256^3 cell of fluid domain I would know how to know the 3 index I,j,k from the cell ID . May you give me some advice ?
thanks in advance

One way is to open up a SpreadSheet View, find the cell with the ID, and then look at the structured coordinates to get the i, j, k indices.

where I have to go to find this ?? I did not found it

Create a new view by clicking the Split Horizontal toolbutton:

In the new window, scroll down to find the SpreadSheet View button and click it. Make sure the volume dataset is selected in the Showing popup menu in the SpreadSheet View. You should see something like this.