A system for analyzing an oilfield having at least one wellsite, each at least one wellsite having a wellbore penetrating a subterranean formation for extracting fluid from an underground reservoir therein, that includes a data collection means for obtaining source data having a plurality of data elements of heterogeneous data types, memory for storing the source data, a functional method configured to perform a function on a dataset of a dataset type to obtain a processed dataset, and a client code configured to process the dataset. The client code includes an object instantiation code configured to use a dataset wrapper class to create the dataset with the dataset type from the source data, and a functional method invocation code configured to call the functional method with the dataset.