Iterating over a dataset to apply specific functions to each row

row-operation.clj

(defmacro apply-filtered
  "Given two sequences, apply a function to each pair of elements when condition is met
  anaphoras n and m exists for each indexed element

  e.g. (apply-filtered / [1 2 3] [1 0 3] when (> m 0)) => (1 nil 1)
  "
  [op a b & condition]
  `(for [x# (range (count ~a))]
    (let [n# (nth ~a x#)
          m# (nth ~b x#)]
      (when (~(second condition) n# m#)
        (~op n# m#)))))

(defmacro apply-rows
  "Apply an operation to each row of the dataset excluding :Date column
   A start row and a condition must be given

  .e.g Divide each row by vector [1 0 3] starting from 0 validating divide by zero
    (apply-rows ds (/ [1 2 3]) 0 (fn [n m] (> m 0))"
  [data operation start cond]
  `(let [raw-data# (incanter.core/$ :all [:not :Date] ~data)
        raw-cols# (incanter.core/col-names raw-data#)
        dates# (incanter.core/$ :all :Date ~data)] 
       (incanter.core/col-names
        (incanter.core/conj-cols
         (for [~'i (range ~start (incanter.core/nrow raw-data#))]
           (apply-filtered
                      ~(first operation)
                      (vec (incanter.core/$ ~'i [:not :Date] raw-data#))
                      ~(second operation)
                      :when ~cond))
         dates#) (conj raw-cols# :Date))))