From 9b24d126c38752514522103c38c800356438b1e2 Mon Sep 17 00:00:00 2001
From: Yang Wang <tiandiwoxin@icloud.com>
Date: Fri, 3 Nov 2017 09:55:51 +0800
Subject: [PATCH] Add some operations (#1816)

* add some ops

* add SquareDifference

* squaredifference

* add SquaredDifference test

* add tests

* add abs

* fix style

* fix style

* fix style

* fix tests

* fix style

* add div

* meet code review

* meet code review

* meet code review