

The equal sign was reserved for this usage.īoth usages have remained common in different programming languages into the early 21st century. ALGOL included a relational operator that tested for equality, allowing constructions like if x = 2 with essentially the same meaning of = as the conditional usage in mathematics. For example, the assignment X = X + 2 increases the value of X by 2.Ī rival programming-language usage was pioneered by the original version of ALGOL, which was designed in 1958 and implemented in 1960. This somewhat resembles the use of = in a mathematical definition, but with different semantics: the expression following = is evaluated first, and may refer to a previous value of X. In Fortran, = serves as an assignment operator: X = 2 sets the value of X to 2. The first important computer programming language to use the equal sign was the original version of Fortran, FORTRAN I, designed in 1954 and implemented in 1957. ), or to express a universal equivalence ( (x + 1)² = x² + 2x + 1). In mathematics, the equal sign can be used as a simple statement of fact in a specific case ( x = 2), or to create definitions ( let x = 2), conditional statements ( if x = 2, then. Usage in mathematics and computer programming The symbol || was used by some and æ (or œ), from the Latin word aequalis meaning equal, was widely used into the 1700s" ( History of Mathematics, University of St Andrews). "The symbol = was not immediately popular. And to avoid the tedious repetition of these words: "is equal to" I will set as I do often in work use, a pair of parallels, or duplicate lines of one length, thus: =, because no 2 things can be more equal.
