determine rsi value over time

hello, unfortunately i couldn't find an existing post in the german forum where the following has been discussed before: i need the value of the rsi-indicator at a certain point of time. the indicator is already initialized and everything else works as well. the pattern-examples of copyrates etc. don't help me right now, because they mostly deal with indicators. for sure the whole thing works via the copybuffer or copyrates, but i'm just stumped at the moment. thanks in advance