linear transformation

linear transformation, in mathematics, a rule for changing one geometric figure (or matrix or vector) into another, using a formula with a specified format. The format must be a linear combination, in which the original components (e.g., the x and y coordinates of each point of the original figure) are changed via the formula ax + by to produce the coordinates of the transformed figure. Examples include flipping the figure over the x or y axis, stretching or compressing it, and rotating it. Some such transformations have an inverse, which undoes their effect.