WELLDEFINED
Well-defined
In mathematics, an expression is well-defined if it is unambiguous and its objects are independent of their representative. More simply, it means that a mathematical statement is sensible and definite. In particular, a function is well-defined if it gives the same result when the form but not the value of an input is changed. The term well-defined is also used to indicate whether a logical statement is unambiguous, and a solution to a partial differential equation is said to be well-defined if it is continuous on the boundary.The above text is a snippet from Wikipedia: Well-defined
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