Finds nthroot of given number

nthroot.clj

(ns kk_samples.nthroot)

(defn abs
      "Calculate the absolute value of number"
      [n]
      (if (neg? n)
          (* -1 n)
          n))

(defn pow
      "Calculates nth power of a number" 
      [number exponent]
      (if (zero? exponent)
          1
          (* number (pow number (- exponent 1)))))

(defn isroot? 
      "Tests if root is close enough to real nth root of number"
      [number n root]
      (let [diff (- (pow root n) number)]
           (if (< (abs diff) 0.001)
               true
               false)))

(defn nthroot
      "finds the nthroot of the given number"
      [number n] 
      (loop [root 1.0] 
            (if(isroot? number n root)
               root
               (recur (/ (+ (* root (- n 1)) (/ number (pow root (- n 1)))) n)))))