https://doi.org/10.1351/goldbook.10047
Measurement results on a system arranged in a \(m \times n\) matrix, with \(m\) objects and \(n\) variables.
Notes:
- By convention a matrix is arranged with \(m\) rows and \(n\) columns.
- Objects are also called "samples", but confusion with physical "test samples" in analytical chemistry should be avoided.
- Variables are also called features, or explanatory variables.
- For multi-way data the data is arranged in a hypercube of \(m \times n_{1} \times n_{2} \times\) …, where \(n_{1}\), \(n_{2}\) … are the kinds of explanatory variable.