# What is approximation?

• (noun): An approximate calculation of quantity or degree or worth.
Synonyms: estimate, estimation, idea

## Approximation

An approximation is a representation of something that is not exact, but still close enough to be useful. Although approximation is most often applied to numbers, it is also frequently applied to such things as mathematical functions, shapes, and physical laws.

### Some articles on approximation:

Model Solid Approximation
... The model solid approximation is a method used for determining the extrema of energy bands in semiconductors ... a semiconductor crystal fluctuates on an atomic scale, the model solid approximation averages these fluctuations out to obtain a constant energy ...
Sparse Approximation
... Sparse approximation (also referred to as sparse decomposition) is the problem of estimating a sparse multi-dimensional vector, satisfying a linear system of equations given ... Sparse approximation techniques have found wide use in applications such as image processing, audio processing, biology, and document analysis ...
Common Integrals In Quantum Field Theory - Integrals That Can Be Approximated By The Method of Stationary Phase
... the limit of small the integral can be evaluated in the stationary phase approximation ... In this approximation the integral is over the path in which the action is a minimum ... Therefore, this approximation recovers the classical limit of mechanics ...
Longest Path Problem - Approximation
... graphs "is notorious for the difficulty of understanding its approximation hardness" ... The best polynomial time approximation algorithm known for this case achieves only a very weak approximation ratio ... there is a big gap between this inapproximability result and the known approximation algorithms for this problem ...

### More definitions of "approximation":

• (noun): The quality of coming near to identity (especially close in quantity).
• (noun): The act of bringing near or bringing together especially the cut edges of tissue.
Synonyms: bringing close together
• (noun): An imprecise or incomplete account.
Example: "Newspapers gave only an approximation of the actual events"