anchor.diff:                 (1+ rowNum))))
       result))
   
  +(defun gradient-descent (X theta y alpha iterTime)
  +  (dotimes (i iterTime theta)
  +    (let ((pd (partial-derivative X theta y)))
  +      (loop for ind from 0 to (1- (length theta)) do
  +           (setf (elt theta ind)
  +                 (- (elt theta ind) (* alpha (elt pd ind)))))
  +      (print theta))))
  +
   ;;; exercise below
   ;;;
   ;;;
  
positive.code: (defun parse-string-to-float (line)
    (with-input-from-string (s line)
      (loop
         :for num := (read s nil nil)
         :while num
         :collect num)))
  
  (defun get-num-out (str)
    (declare (inline parse-string-to-float))
  
negative.code: (defvar *X*)
  (setf *X*
        (let ((temp
               (loop for ar in (read-data "./testData.txt") collect
                    (list 1 (elt ar 0)))))
          (make-array (list (length temp) (length (car temp))) :initial-contents temp)))
  
  (defvar *y*)
  (setf *y*
        (loop for ar in (read-data "./testData.txt") collect
             (elt ar 1)))
  
  (defvar *theta*)
  (setf *theta* (make-array 2 :initial-element 0))
  
  (compute-cost *X* *theta* *y*)
  (gradient-descent *X* *theta* *y* 0.01 1500)
  