How would you get the ROC (rate of change) of an indicator in Ninja? I was trying to address the problem of only wanting crosses in indicators like MACD that were above a certain angle. This can not be done directly because angle is not an output of the indicator. However I deduced a work around of using the ROC of the indicator and requiring that it be over a certain level. This should produce reasonable results assuming you don't need exact angles.
I have tried this on StockCharts and have liked the scan results so far. (one day)

There it looks like this: ... [TSI(25,13,7) x TSI Signal(25,13,7)] and [ROC(14, TSI (25,13,7)) > 400]

But now I would like to backtest and see if there is really any correlation between what I am trying to do and actual improved trading results. Does a sharper angle cross of an indicator really produce better entries?

To do that I need to know how to write the above into a Ninja strategy.

Can anyone tell me how that is done? Thanks

So I figured this out.