Mathematical Row

This element is a wrapper containing the presentation expression mi. It creates a single string without spaces consisting of the individual elements described within it. It can be used to create a single variable by concatenating other variables into a single string. It is used to create linking variables composed of multiple non-contiguous parts, or to define unique strings for various category values of a single variable. This is an element taken from MathML. The example shows the use of mrow in the context of a code based on two separate variables.