\doteqThe symbol \doteq is used to denote a relation that is defined or agreed upon to be equal, often used in contexts where an equation is defined or approximated. It is commonly used in mathematical texts to indicate that two expressions are defined to be equal or are approximately equal under certain conditions.
Defines x to be equal to y by agreement or definition.
x \doteq yIndicates that f(x) is approximately equal to g(x) with an error term of order h squared.
f(x) \doteq g(x) + O(h^2)Defines matrix A to be equal to matrix B by definition or agreement.
A \doteq B