Thanks for the reply! I could not see file called Workshop4.c, only Worhshop_a reference in the above link you provided, where is this file?

Also, I did find the following in Zorro help at
https://zorro-trader.com/manual/en/macd.htm


// when the MACD Histogram goes above zero, buy long
if (crossOver(macdHist(12,26,9),constant(0)))
buyLong(0);
// sell when it goes below zero
if (crossUnder(macdHist(12,26,9),constant(0)))
sellLong(0);


But it doesn't compile, throwing error about macdHist cannot be found. Maybe it's in some external h file?