Numerical stability is a notion in numerical analysis. The GPS equations can be solved by numerical and analytical methods. Iterative methods are more common than direct methods in numerical analysis. Subsequent sections describe methods suitable for numerical evaluation on large matrices. They can be solved by algebraic or numerical methods. One approach to complexity theory of numerical analysis is information based complexity. A histogram is an approximate representation of the distribution of numerical or categorical data. Psychological tests measure specific abilities, such as clerical, perceptual, numerical, or spatial aptitude. Letters may also have a numerical or quantitative value. Examples of verified analytic solutions along with precise numerical values are available. Performing subtraction is one of the simplest numerical tasks. Box plot is a method for graphically depicting groups of numerical data. This is supported by numerical simulations. This is a list of numerical analysis topics. The field of numerical analysis includes many sub-disciplines.