I think you’re asking for too much at one time and I’m not completely sure I understand what you’re looking for and I’m afraid if I did it would take several far too long to explain how to set it up, code it and test it. This forum is mostly users helping other users.
I wanted to create a custom fields “rank” which will contain a digital value (ex: $value).
That’s the easy part.
I want to use this value to classify/sort articles by its position on a page.
Sort them by the position on the page? Do you mean sort the posts by this field?
-need to compare all the field value custom “Rank” with all sections to avoid duplicates.
Sections? What do you mean by sections?
-compare the values to sort the articles with categories and tags according to its order of rank (descending or ascending)
Not sure what you are sorting here or by what.
-If the value exists, shifted all the other value greater than n in n + 1 (ex: If value = 12 and 12 exists for an article, replace value in A 12 + 1, and any other value for n + 1)
?
