Normally when using Expert Advisors in MetaTrader, you would export strategies as Expert Advisors and attach each Expert to a chart window. When trading multiple strategies opening and managing all the charts quickly becomes a hassle.
To save you the hassle of operating multiple experts and charts, EA Studio introduces Portfolio Experts. Portfolio Experts hold multiple strategies within them and trade those strategies on a single MetaTrader chart.
Because the Portfolio Expert trades multiple strategies simultaneously, it must know which position belongs to which strategy. This is done by assigning a different Magic Number to each strategy in the portfolio. You can set the base (first 3 digits) of the Magic Number when you attach the Portfolio Expert to the chart. The full magic number for each strategy will be something like 100001 where 100 is the base magic number, and 001 is the strategy number.
MetaTrader shows a dialogue window when you attach an Expert to a chart. In this window, under the Inputs tab, there is a value for the base of the Magic numbers of the strategies in the Portfolio Expert.
You can change this number to whatever you like.
Then when the Portfolio Expert opens positions, you can see the strategy's Magic Number in the Comment column of the position.
You can see how each Magic number is set in the comment, and each Magic number starts with 100 because that is the value we set when we were attaching the Portfolio Expert to the chart in the first picture.
Currently, one Portfolio works only on one market. If you want to trade multiple markets, you can create separate portfolios for each market.