modify readme and changelog

Author: kortirso

CHANGELOG.md

@@ -4,6 +4,10 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
+## Unreleased
+### Modified
+- Linear Regression, fit with gradient descent
+
 ## [0.1.2] - 2018-11-22
 ### Added
 - CHANGELOG.md file

README.md

@@ -33,12 +33,18 @@ Initialize predictor with data:
   predictor = Linear.new([1, 2, 3, 4], [3, 6, 10, 15])
 ```
 
-Fit data set:
+Fit data set with least squares method:
 
 ```elixir
   predictor = predictor |> Linear.fit
 ```
 
+Fit data set with gradient descent method:
+
+```elixir
+  predictor = predictor |> Linear.fit([method: "gradient descent"])
+```
+
 Predict using the linear model:
 
 ```elixir

lib/learn_kit/regression/linear.ex

@@ -49,7 +49,7 @@ defmodule LearnKit.Regression.Linear do
   end
 
   @doc """
-  Fit train data with least squares method
+  Fit train data
 
   ## Parameters