From 35562c0698b87f82ff0d2791885f43e2272aeb55 Mon Sep 17 00:00:00 2001
From: Patrice Matz <ofjokg@gmail.com>
Date: Sat, 9 Dec 2017 14:02:57 +0100
Subject: [PATCH] -fixed mid_diff

---
 SCE/SCE/DIFF.cpp | 9 +++++++--
 SCE/SCE/DIFF.h   | 2 --
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/SCE/SCE/DIFF.cpp b/SCE/SCE/DIFF.cpp
index fe8ec06..497e550 100644
--- a/SCE/SCE/DIFF.cpp
+++ b/SCE/SCE/DIFF.cpp
@@ -3,7 +3,6 @@ using namespace std;
 
 DIFF::DIFF()
 {
-	y1values.resize(yvalues.size());
 }
 
 
@@ -70,10 +69,16 @@ vector<long double> DIFF::mid_diff(vector<long double>y, vector<long double>x)
 
 	temp.at(i) = (y.at(i + 1) - y.at(i)) / (x.at(i + 1) - x.at(i));
 	i++;
-	for (; i < y.size() - 1; i++)
+	temp.at(i) = (y.at(i + 1) - y.at(i)) / (x.at(i + 1) - x.at(i));
+	temp.at(i) += (y.at(i + 1) - y.at(i - 1)) / (x.at(i + 1) - x.at(i - 1));
+	temp.at(i) /= 2;
+	for (; i < y.size() - 2; ++i)
 	{
 		temp.at(i) = (y.at(i + 1) - y.at(i - 1)) / (x.at(i + 1) - x.at(i - 1));
 	}
+	temp.at(i) += (y.at(i) - y.at(i - 1)) / (x.at(i) - x.at(i - 1));
+	temp.at(i) /= 2;
+	i++;
 	temp.at(i) = (y.at(i) - y.at(i - 1)) / (x.at(i) - x.at(i - 1));
 	
 	return temp;
diff --git a/SCE/SCE/DIFF.h b/SCE/SCE/DIFF.h
index 1e448f6..682b522 100644
--- a/SCE/SCE/DIFF.h
+++ b/SCE/SCE/DIFF.h
@@ -7,8 +7,6 @@ class DIFF
 public:
 	vector<long double> xvalues = {0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250};
 	vector<long double> yvalues = {0, 2926, 10170, 21486, 33835, 45251, 55634, 65038, 73461, 80905, 87368, 92852, 97355, 100878, 103422, 104986, 106193, 110246, 119626, 136106, 162095, 199506, 238775, 277065, 314375, 350704};
-	vector<long double> y1values; //y-values of 1st derivative
-	vector<long double> y2values; //y-values of 2nd derivative
 	vector<long double> diff();