Function symbolicEqual #

Attempts to determine if two expressions are symbolically equal, i.e. one is the result of valid algebraic manipulations on the other. Currently, this simply checks if the difference of the two expressions simplifies down to 0. So there are two important caveats:

  1. whether two expressions are symbolically equal depends on the manipulations allowed. Therefore, this function takes an optional third argument, which are the options that control the behavior as documented for the simplify() function.
  2. it is in general intractable to find the minimal simplification of an arbitrarily complicated expression. So while a true value of symbolicEqual ensures that the two expressions can be manipulated to match each other, a false value does not absolutely rule this out.

Syntax #

symbolicEqual(expr1, expr2)
symbolicEqual(expr1, expr2, options)

Parameters #

Parameter Type Description
expr1 Node | string The first expression to compare
expr2 Node | string The second expression to compare
options Object Optional option object, passed to simplify

Returns #

Type Description
boolean Returns true if a valid manipulation making the expressions equal is found.

Throws #

Type | Description —- | ———–

Examples #

symbolicEqual('x*y', 'y*x') // Returns true
symbolicEqual('x*y', 'y*x', {context: {multiply: {commutative: false}}}) // Returns false
symbolicEqual('x/y', '(y*x^(-1))^(-1)') // Returns true
symbolicEqual('abs(x)','x') // Returns false
symbolicEqual('abs(x)','x', simplify.positiveContext) // Returns true

See also #

simplify, evaluate

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