Function applyAngle

src/compute-engine/boxed-expression/trigonometry.ts:225–242

(
  angle: Expression,
  fn: (x: number) => number | Complex | Expression,
  bigFn?: (x: BigDecimal) => BigDecimal | Complex | number | Expression,
  complexFn?: (x: Complex) => number | Complex
)

  ],
];

function applyAngle(
  angle: Expression,
  fn: (x: number) => number | Complex | Expression,
  bigFn?: (x: BigDecimal) => BigDecimal | Complex | number | Expression,
  complexFn?: (x: Complex) => number | Complex
): Expression | undefined {
  const angle0 = canonicalAngle(angle);
  if (angle0 === undefined) return undefined;
  // `apply` below declines anything that is not a number LITERAL, and an
  // expression with unknowns cannot become one — so numericizing it first is
  // waste, and on a nested tree of user-function applications an exponential
  // one. (This is the same walk `constructibleValues` skips on the exact path;
  // `applyAngle` is the `.N()` path's copy of it.)
  if (angle0.unknowns.length > 0) return undefined;
  const theta = angle0.N();
  // `apply`'s machine/bignum handlers can also yield an already-boxed
  // expression (e.g. `ce.ComplexInfinity` for a `Tan` pole), which it boxes
  // through `ce.number`; its public signature is narrower, so cast here.
  return apply(
    theta,