Method on @infsup: sec (X)

Compute the secant in radians, that is the reciprocal cosine.

Accuracy: The result is a tight enclosure.

sec (infsup (1))
  ⇒ ans ⊂ [1.8508, 1.8509]

See also: @infsup/cos, @infsup/csc, @infsup/cot.

Package: interval