cljs.math/get-exponent

function

since v1.11.50

Edit

---

Source docstring:

Returns the exponent of d.
If d is ##NaN, ##Inf, ##-Inf => max_Float64_exponent + 1
If d is zero or subnormal => min_Float64_exponent - 1
See: https://docs.oracle.com/javase/8/docs/api/java/lang/Math.html#getExponent-double-

(defn ^number get-exponent
  {:added "1.11.10"}
  [d]
  (cond
    (or ^boolean (js/isNaN d) (not ^boolean (js/isFinite d))) (inc EXP-MAX)
    (zero? d) (dec EXP-MIN)
    :default (let [a (js/ArrayBuffer. 8)
                   f (js/Float64Array. a)
                   i (js/Uint32Array. a)
                   hi (if little-endian? 1 0)]
               (aset f 0 d)
               (- (bit-shift-right (bit-and (aget i hi) EXP-BITMASK32) (dec SIGNIFICAND-WIDTH32)) EXP-BIAS))))

---