Fetching stock data using a parameterised Execute R operator

I'm currently delivering data science lectures at the University of Chichester and RapidMiner is part of what I use to teach. And very good it is too. I recently found myself helping my students to get some up to date stock market data. Rather than manually downloading this, I thought I would use RapidMiner with the tidyquant R package and do it automatically. The Finance and Economics Extension seems to be out of date so isn't an option.

My idea was to define a list of stock symbols such as "AAPL", "BTC-USD" and so on and run the Execute R operator in a loop with each symbol individually.

It turns out there isn't a way to parameterise the Execute R operator so I had to invent one.

Basically, I use the Loop Parameters operator to set multiple values for a macro located inside it. This macro is used to create a one row example set with the value of the macro. This example set is then passed to the Execute R operator where the R script uses it as a parameter to drive the rest of the script. It's clunky but it works.

This approach could be adapted to allow R scripts to be run as part of a more complex modelling process. Relatively tough to do but feasible.

Here's a link to the process.

You'll need the R Scripting extension and you will also need to ensure that R is running on your machine with the data.table, tidyverse and tidyquant R packages all installed.

If RapidMiner enhances the Execute R operator to take parameters, (which would be a good enhancement), then this work around will not be needed anymore.