Added(A)/Deleted(D) following books

 M  A_Textbook_of_Electrical_Technology_:_AC_and_DC_Machines_(Volume_-_2)_by_A_K_Theraja_B_L_Thereja/chapter25_7.ipynb
M  A_Textbook_of_Electrical_Technology_:_AC_and_DC_Machines_(Volume_-_2)_by_A_K_Theraja_B_L_Thereja/chapter26_7.ipynb
M  A_Textbook_of_Electrical_Technology_:_AC_and_DC_Machines_(Volume_-_2)_by_A_K_Theraja_B_L_Thereja/chapter27_7.ipynb
M  A_Textbook_of_Electrical_Technology_:_AC_and_DC_Machines_(Volume_-_2)_by_A_K_Theraja_B_L_Thereja/chapter28_7.ipynb
M  A_Textbook_of_Electrical_Technology_:_AC_and_DC_Machines_(Volume_-_2)_by_A_K_Theraja_B_L_Thereja/chapter29_7.ipynb
M  A_Textbook_of_Electrical_Technology_:_AC_and_DC_Machines_(Volume_-_2)_by_A_K_Theraja_B_L_Thereja/chapter30_7.ipynb
M  A_Textbook_of_Electrical_Technology_:_AC_and_DC_Machines_(Volume_-_2)_by_A_K_Theraja_B_L_Thereja/chapter31_7.ipynb
M  A_Textbook_of_Electrical_Technology_:_AC_and_DC_Machines_(Volume_-_2)_by_A_K_Theraja_B_L_Thereja/chapter32_7.ipynb
M  A_Textbook_of_Electrical_Technology_:_AC_and_DC_Machines_(Volume_-_2)_by_A_K_Theraja_B_L_Thereja/chapter33_7.ipynb
M  A_Textbook_of_Electrical_Technology_:_AC_and_DC_Machines_(Volume_-_2)_by_A_K_Theraja_B_L_Thereja/chapter34_7.ipynb
M  A_Textbook_of_Electrical_Technology_:_AC_and_DC_Machines_(Volume_-_2)_by_A_K_Theraja_B_L_Thereja/chapter35_7.ipynb
M  A_Textbook_of_Electrical_Technology_:_AC_and_DC_Machines_(Volume_-_2)_by_A_K_Theraja_B_L_Thereja/chapter36_7.ipynb
M  A_Textbook_of_Electrical_Technology_:_AC_and_DC_Machines_(Volume_-_2)_by_A_K_Theraja_B_L_Thereja/chapter37_7.ipynb
M  A_Textbook_of_Electrical_Technology_:_AC_and_DC_Machines_(Volume_-_2)_by_A_K_Theraja_B_L_Thereja/chapter38_7.ipynb
M  A_Textbook_of_Electrical_Technology_:_AC_and_DC_Machines_(Volume_-_2)_by_A_K_Theraja_B_L_Thereja/chapter39_7.ipynb
M  A_Textbook_of_Electrical_Technology_:_AC_and_DC_Machines_(Volume_-_2)_by_A_K_Theraja_B_L_Thereja/screenshots/chapter29example32_7.png
M  A_Textbook_of_Electrical_Technology_:_AC_and_DC_Machines_(Volume_-_2)_by_A_K_Theraja_B_L_Thereja/screenshots/chapter29example33_7.png
M  A_Textbook_of_Electrical_Technology_:_AC_and_DC_Machines_(Volume_-_2)_by_A_K_Theraja_B_L_Thereja/screenshots/chapter32example30_7.png
M  Manufacturing_Engineering_&_Technology_by_S._Kalpakjian_and_S._R._Schmid/CHAPTER10.ipynb
M  Manufacturing_Engineering_&_Technology_by_S._Kalpakjian_and_S._R._Schmid/CHAPTER13.ipynb
M  Manufacturing_Engineering_&_Technology_by_S._Kalpakjian_and_S._R._Schmid/CHAPTER14.ipynb
M  Manufacturing_Engineering_&_Technology_by_S._Kalpakjian_and_S._R._Schmid/CHAPTER15.ipynb
M  Manufacturing_Engineering_&_Technology_by_S._Kalpakjian_and_S._R._Schmid/CHAPTER16.ipynb
M  Manufacturing_Engineering_&_Technology_by_S._Kalpakjian_and_S._R._Schmid/CHAPTER17.ipynb
M  Manufacturing_Engineering_&_Technology_by_S._Kalpakjian_and_S._R._Schmid/CHAPTER18.ipynb
M  Manufacturing_Engineering_&_Technology_by_S._Kalpakjian_and_S._R._Schmid/CHAPTER2.ipynb
M  Manufacturing_Engineering_&_Technology_by_S._Kalpakjian_and_S._R._Schmid/CHAPTER20.ipynb
M  Manufacturing_Engineering_&_Technology_by_S._Kalpakjian_and_S._R._Schmid/CHAPTER22.ipynb
M  Manufacturing_Engineering_&_Technology_by_S._Kalpakjian_and_S._R._Schmid/CHAPTER23.ipynb
M  Manufacturing_Engineering_&_Technology_by_S._Kalpakjian_and_S._R._Schmid/CHAPTER25.ipynb
M  Manufacturing_Engineering_&_Technology_by_S._Kalpakjian_and_S._R._Schmid/CHAPTER28.ipynb
M  Manufacturing_Engineering_&_Technology_by_S._Kalpakjian_and_S._R._Schmid/CHAPTER32.ipynb
M  Manufacturing_Engineering_&_Technology_by_S._Kalpakjian_and_S._R._Schmid/CHAPTER36.ipynb
M  Manufacturing_Engineering_&_Technology_by_S._Kalpakjian_and_S._R._Schmid/CHAPTER9.ipynb
M  Manufacturing_Engineering_&_Technology_by_S._Kalpakjian_and_S._R._Schmid/screenshots/CHAP10.png
M  Manufacturing_Engineering_&_Technology_by_S._Kalpakjian_and_S._R._Schmid/screenshots/CHAP16.png
M  Manufacturing_Engineering_&_Technology_by_S._Kalpakjian_and_S._R._Schmid/screenshots/CHAP23.png
M  RCC_Theory_and_Design_by_M._G._Shah_and_C._M._Kale/Chapter1.ipynb
M  RCC_Theory_and_Design_by_M._G._Shah_and_C._M._Kale/Chapter10.ipynb
M  RCC_Theory_and_Design_by_M._G._Shah_and_C._M._Kale/Chapter11.ipynb
M  RCC_Theory_and_Design_by_M._G._Shah_and_C._M._Kale/Chapter12.ipynb
M  RCC_Theory_and_Design_by_M._G._Shah_and_C._M._Kale/Chapter13.ipynb
M  RCC_Theory_and_Design_by_M._G._Shah_and_C._M._Kale/Chapter14.ipynb
M  RCC_Theory_and_Design_by_M._G._Shah_and_C._M._Kale/Chapter15.ipynb
M  RCC_Theory_and_Design_by_M._G._Shah_and_C._M._Kale/Chapter16.ipynb
M  RCC_Theory_and_Design_by_M._G._Shah_and_C._M._Kale/Chapter17.ipynb
M  RCC_Theory_and_Design_by_M._G._Shah_and_C._M._Kale/Chapter18.ipynb
M  RCC_Theory_and_Design_by_M._G._Shah_and_C._M._Kale/Chapter19.ipynb
M  RCC_Theory_and_Design_by_M._G._Shah_and_C._M._Kale/Chapter2.ipynb
M  RCC_Theory_and_Design_by_M._G._Shah_and_C._M._Kale/Chapter3.ipynb
M  RCC_Theory_and_Design_by_M._G._Shah_and_C._M._Kale/Chapter4.ipynb
M  RCC_Theory_and_Design_by_M._G._Shah_and_C._M._Kale/Chapter5.ipynb
M  RCC_Theory_and_Design_by_M._G._Shah_and_C._M._Kale/Chapter7.ipynb
M  RCC_Theory_and_Design_by_M._G._Shah_and_C._M._Kale/Chapter8.ipynb
M  RCC_Theory_and_Design_by_M._G._Shah_and_C._M._Kale/Chapter9.ipynb
M  RCC_Theory_and_Design_by_M._G._Shah_and_C._M._Kale/screenshots/11.4.png
M  RCC_Theory_and_Design_by_M._G._Shah_and_C._M._Kale/screenshots/13.1.png
M  RCC_Theory_and_Design_by_M._G._Shah_and_C._M._Kale/screenshots/15.4.png
M  Strength_Of_Materials_by_S_S_Bhavikatti/chapter_no.10_9.ipynb
M  Strength_Of_Materials_by_S_S_Bhavikatti/chapter_no.2_9.ipynb
M  Strength_Of_Materials_by_S_S_Bhavikatti/chapter_no.3_9.ipynb
M  Strength_Of_Materials_by_S_S_Bhavikatti/chapter_no.4_9.ipynb
M  Strength_Of_Materials_by_S_S_Bhavikatti/chapter_no.5_9.ipynb
M  Strength_Of_Materials_by_S_S_Bhavikatti/chapter_no.6_9.ipynb
M  Strength_Of_Materials_by_S_S_Bhavikatti/chapter_no.7_9.ipynb
M  Strength_Of_Materials_by_S_S_Bhavikatti/chapter_no.8_9.ipynb
M  Strength_Of_Materials_by_S_S_Bhavikatti/chapter_no.9_9.ipynb
M  Strength_Of_Materials_by_S_S_Bhavikatti/screenshots/BMD_1.JPG
M  Strength_Of_Materials_by_S_S_Bhavikatti/screenshots/SFD2_1.JPG
M  Strength_Of_Materials_by_S_S_Bhavikatti/screenshots/S_F_D_1_1.JPG
M  Unified_Physics_by_S.L._Gupta,_Sanjeev_Gupta/Chapter1.ipynb
M  Unified_Physics_by_S.L._Gupta,_Sanjeev_Gupta/Chapter10.ipynb
M  Unified_Physics_by_S.L._Gupta,_Sanjeev_Gupta/Chapter11.ipynb
M  Unified_Physics_by_S.L._Gupta,_Sanjeev_Gupta/Chapter12.ipynb
M  Unified_Physics_by_S.L._Gupta,_Sanjeev_Gupta/Chapter14.ipynb
M  Unified_Physics_by_S.L._Gupta,_Sanjeev_Gupta/Chapter15.ipynb
M  Unified_Physics_by_S.L._Gupta,_Sanjeev_Gupta/Chapter16.ipynb
M  Unified_Physics_by_S.L._Gupta,_Sanjeev_Gupta/Chapter2.ipynb
M  Unified_Physics_by_S.L._Gupta,_Sanjeev_Gupta/Chapter3.ipynb
M  Unified_Physics_by_S.L._Gupta,_Sanjeev_Gupta/Chapter4.ipynb
M  Unified_Physics_by_S.L._Gupta,_Sanjeev_Gupta/Chapter5.ipynb
M  Unified_Physics_by_S.L._Gupta,_Sanjeev_Gupta/Chapter6.ipynb
M  Unified_Physics_by_S.L._Gupta,_Sanjeev_Gupta/Chapter7.ipynb
M  Unified_Physics_by_S.L._Gupta,_Sanjeev_Gupta/Chapter9.ipynb
M  Unified_Physics_by_S.L._Gupta,_Sanjeev_Gupta/screenshots/1.png
M  Unified_Physics_by_S.L._Gupta,_Sanjeev_Gupta/screenshots/2.png
M  Unified_Physics_by_S.L._Gupta,_Sanjeev_Gupta/screenshots/3.png
M  _A_Textbook_of_Electrical_Technology:Transmission,Distribution_And_Utilisation(Vol_III)_by_B.L.Thareja_and_A.K.Thareja/chapter40.ipynb
M  _A_Textbook_of_Electrical_Technology:Transmission,Distribution_And_Utilisation(Vol_III)_by_B.L.Thareja_and_A.K.Thareja/chapter41.ipynb
M  _A_Textbook_of_Electrical_Technology:Transmission,Distribution_And_Utilisation(Vol_III)_by_B.L.Thareja_and_A.K.Thareja/chapter43.ipynb
M  _A_Textbook_of_Electrical_Technology:Transmission,Distribution_And_Utilisation(Vol_III)_by_B.L.Thareja_and_A.K.Thareja/chapter44.ipynb
M  _A_Textbook_of_Electrical_Technology:Transmission,Distribution_And_Utilisation(Vol_III)_by_B.L.Thareja_and_A.K.Thareja/chapter45.ipynb
M  _A_Textbook_of_Electrical_Technology:Transmission,Distribution_And_Utilisation(Vol_III)_by_B.L.Thareja_and_A.K.Thareja/chapter46.ipynb
M  _A_Textbook_of_Electrical_Technology:Transmission,Distribution_And_Utilisation(Vol_III)_by_B.L.Thareja_and_A.K.Thareja/chapter47.ipynb
M  _A_Textbook_of_Electrical_Technology:Transmission,Distribution_And_Utilisation(Vol_III)_by_B.L.Thareja_and_A.K.Thareja/chapter49.ipynb
M  _A_Textbook_of_Electrical_Technology:Transmission,Distribution_And_Utilisation(Vol_III)_by_B.L.Thareja_and_A.K.Thareja/chapter50.ipynb
M  _A_Textbook_of_Electrical_Technology:Transmission,Distribution_And_Utilisation(Vol_III)_by_B.L.Thareja_and_A.K.Thareja/screenshots/figure_1.png
M  _A_Textbook_of_Electrical_Technology:Transmission,Distribution_And_Utilisation(Vol_III)_by_B.L.Thareja_and_A.K.Thareja/screenshots/figure_2.png
M  _A_Textbook_of_Electrical_Technology:Transmission,Distribution_And_Utilisation(Vol_III)_by_B.L.Thareja_and_A.K.Thareja/screenshots/figure_3.png
M  f_by_134/1_An_overview_of_C++_1.ipynb
M  f_by_134/screenshots/anshul.png
M  f_by_134/screenshots/anshul_1.png
M  f_by_134/screenshots/anshul_2.png
M  f_by_Gayakwad/abhishek.ipynb
M  f_by_Gayakwad/screenshots/blank1.png
M  f_by_Gayakwad/screenshots/blank1_(another_copy).png
M  f_by_Gayakwad/screenshots/blank1_(copy).png
M  f_by_df/README.txt
M  f_by_df/abhishek.ipynb
M  f_by_df/abhishek_1.ipynb
M  f_by_df/abhishek_2.ipynb
M  f_by_df/screenshots/anshul.png
M  f_by_df/screenshots/anshul_1.png
M  f_by_df/screenshots/anshul_2.png
M  f_by_df/screenshots/array_factor.png
M  f_by_df/screenshots/blank1.png
M  f_by_df/screenshots/blog.png
M  f_by_df/screenshots/sai.png
M  f_by_df/screenshots/snippet1.png
M  f_by_df/screenshots/srinivas.png
M  hfgd_by_Gayakwad/README.txt
M  hfgd_by_Gayakwad/abhishek.ipynb
M  hfgd_by_Gayakwad/screenshots/anshul.png
M  hfgd_by_Gayakwad/screenshots/anshul_1.png
M  hfgd_by_Gayakwad/screenshots/anshul_2.png
M  mathematics_by_df/aditya.ipynb
M  mathematics_by_df/screenshots/anshul.png
M  mathematics_by_df/screenshots/array_factor.png
M  mathematics_by_df/screenshots/array_factor_1.png
M  rewrew_by_J._B._Gupta/README.txt
M  rewrew_by_J._B._Gupta/aviral.ipynb
M  rewrew_by_J._B._Gupta/screenshots/array_factor.png
M  rewrew_by_J._B._Gupta/screenshots/book.png
M  rewrew_by_J._B._Gupta/screenshots/error.png
M  sample_notebooks/IshitaTewari/Chapter08.ipynb
M  sample_notebooks/JeevanLal/aditya.ipynb
A  sample_notebooks/SINDHUARROJU/Chapter3.ipynb
M  sample_notebooks/SandhyaArroju/Chapter7.ipynb
M  sample_notebooks/asmitaasmita/1_An_overview_of_C++_2.ipynb
M  testing_by_df/README.txt

5 files changed, 659 insertions, 0 deletions

diff --git a/sample_notebooks/IshitaTewari/Chapter08.ipynb b/sample_notebooks/IshitaTewari/Chapter08.ipynb
index d93a3033..d93a3033 100644..100755
--- a/sample_notebooks/IshitaTewari/Chapter08.ipynb
+++ b/sample_notebooks/IshitaTewari/Chapter08.ipynb
diff --git a/sample_notebooks/JeevanLal/aditya.ipynb b/sample_notebooks/JeevanLal/aditya.ipynb
index a77ec491..a77ec491 100644..100755
--- a/sample_notebooks/JeevanLal/aditya.ipynb
+++ b/sample_notebooks/JeevanLal/aditya.ipynb
diff --git a/sample_notebooks/SINDHUARROJU/Chapter3.ipynb b/sample_notebooks/SINDHUARROJU/Chapter3.ipynb
new file mode 100755
index 00000000..9f186c2a
--- /dev/null
+++ b/sample_notebooks/SINDHUARROJU/Chapter3.ipynb
@@ -0,0 +1,659 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# 3: Crystal Planes,X-ray Diffraction and Defects in Solids"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example number 1, Page number 3-19"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 5,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "glancing angle is 21 degrees\n"
+     ]
+    }
+   ],
+   "source": [
+    "#importing modules\n",
+    "import math\n",
+    "from __future__ import division\n",
+    "\n",
+    "#Variable declaration\n",
+    "a=0.28;         #lattice spacing(nm)\n",
+    "lamda=0.071;    #wavelength of X-rays(nm)\n",
+    "h=1;\n",
+    "k=1;\n",
+    "l=0;\n",
+    "n=2;\n",
+    "\n",
+    "#Calculation\n",
+    "d=a/math.sqrt(h**2+k**2+l**2);           \n",
+    "sintheta=n*lamda/(2*d);\n",
+    "theta=math.asin(sintheta)*180/math.pi;           #glancing angle(degrees)\n",
+    "\n",
+    "#Result\n",
+    "print \"glancing angle is\",int(theta),\"degrees\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example number 2, Page number 3-19"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 8,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "wavelength of X-rays is 0.0842 nm\n",
+      "maximum order of diffraction is 7\n"
+     ]
+    }
+   ],
+   "source": [
+    "#importing modules\n",
+    "import math\n",
+    "from __future__ import division\n",
+    "\n",
+    "#Variable declaration\n",
+    "d=0.282;       #lattice spacing(nm)\n",
+    "theta=(8+(35/60))*math.pi/180;     #glancing angle(radian)\n",
+    "n=1;           #order\n",
+    "\n",
+    "#Calculation\n",
+    "lamda=2*d*math.sin(theta)/n;    #wavelength of X-rays(nm)\n",
+    "n=2*d/lamda;                    #maximum order of diffraction\n",
+    "\n",
+    "#Result\n",
+    "print \"wavelength of X-rays is\",round(lamda,4),\"nm\"\n",
+    "print \"maximum order of diffraction is\",int(round(n))"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example number 3, Page number 3-20"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 15,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "fraction of vacancy sites is 8.466 *10**-7\n"
+     ]
+    }
+   ],
+   "source": [
+    "#importing modules\n",
+    "import math\n",
+    "from __future__ import division\n",
+    "\n",
+    "#Variable declaration\n",
+    "T1=773;            #temperature(K)\n",
+    "T2=1273;           #temperature(K)\n",
+    "f=10**-10;         #fraction of vacant sites\n",
+    "\n",
+    "#Calculation\n",
+    "x=round(T1*math.log(f)/T2,3);\n",
+    "N=math.exp(x);    #fraction of vacancy sites\n",
+    "\n",
+    "#Result\n",
+    "print \"fraction of vacancy sites is\",round(N*10**7,3),\"*10**-7\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example number 4, Page number 3-21"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": true
+   },
+   "outputs": [],
+   "source": [
+    "#importing modules\n",
+    "import math\n",
+    "from __future__ import division\n",
+    "\n",
+    "#Variable declaration\n",
+    "h1=1;\n",
+    "k1=0;\n",
+    "l1=0;    #miller indices of (100)\n",
+    "h2=1;\n",
+    "k2=1;\n",
+    "l2=0;    #miller indices of (110)\n",
+    "h3=1;\n",
+    "k3=1;\n",
+    "l3=1;    #miller indices of (111)\n",
+    "a=1;     #assume\n",
+    "\n",
+    "#Calculation\n",
+    "d100=a/math.sqrt(h1**2+k1**2+l1**2);    #spacing(nm)\n",
+    "d110=a/math.sqrt(h2**2+k2**2+l2**2);    #spacing(nm)\n",
+    "d111=a/math.sqrt(h3**2+k3**2+l3**2);    #spacing(nm)\n",
+    "\n",
+    "def lcm(x, y):\n",
+    "    if x > y:\n",
+    "        greater = x\n",
+    "    else:\n",
+    "        greater = y\n",
+    "    while(True):\n",
+    "        if((greater % x == 0) and (greater % y == 0)):\n",
+    "            lcm = greater\n",
+    "            break\n",
+    "        greater += 1\n",
+    "        \n",
+    "    return lcm\n",
+    "\n",
+    "lcm=lcm(1/d110,1/d111);\n",
+    "#d100=d100*lcm;\n",
+    "#d110=d110*lcm;\n",
+    "#d111=d111*lcm;      #ratio d100:d110:d111\n",
+    "\n",
+    "#Result\n",
+    "print \"ratio d100:d110:d111 is\",d100,d110,d111"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example number 5, Page number 3-21"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 19,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "lattice parameter is 3.522 angstrom\n"
+     ]
+    }
+   ],
+   "source": [
+    "#importing modules\n",
+    "import math\n",
+    "from __future__ import division\n",
+    "\n",
+    "#Variable declaration\n",
+    "n=1;     #order\n",
+    "theta=38.2*math.pi/180;     #glancing angle(radian)\n",
+    "lamda=1.54;                 #wavelength(angstrom)\n",
+    "h=2;\n",
+    "k=2;\n",
+    "l=0;\n",
+    "\n",
+    "#Calculation\n",
+    "a=math.sqrt(h**2+k**2+l**2);\n",
+    "d=n*lamda*a/(2*math.sin(theta));       #lattice parameter(angstrom)\n",
+    "\n",
+    "#Result\n",
+    "print \"lattice parameter is\",round(d,3),\"angstrom\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example number 6, Page number 3-22"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 22,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "maximum order of diffraction is 2\n"
+     ]
+    }
+   ],
+   "source": [
+    "#importing modules\n",
+    "import math\n",
+    "from __future__ import division\n",
+    "\n",
+    "#Variable declaration\n",
+    "d=1.6;       #lattice spacing(angstrom)\n",
+    "theta=90*math.pi/180;     #glancing angle(radian)\n",
+    "lamda=1.5;    #wavelength of X-rays(angstrom)\n",
+    "\n",
+    "#Calculation\n",
+    "n=2*d*math.sin(theta)/lamda;       #maximum order of diffraction \n",
+    "\n",
+    "#Result\n",
+    "print \"maximum order of diffraction is\",int(n)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example number 7, Page number 3-22"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 26,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "length is 0.287 *10**-9 m\n",
+      "volume of unit cell is 0.02366 *10**-27 m**3\n",
+      "answer for volume given in the book varies due to rounding off errors\n",
+      "radius of atom is 0.1243 *10**-9 m\n"
+     ]
+    }
+   ],
+   "source": [
+    "#importing modules  \n",
+    "import math\n",
+    "from __future__ import division\n",
+    "\n",
+    "#Variable declaration\n",
+    "d=0.203*10**-9;       #lattice spacing(m)\n",
+    "h=1;\n",
+    "k=1;\n",
+    "l=0;          #miller indices of (110)\n",
+    "lamda=1.5;    #wavelength of X-rays(angstrom)\n",
+    "\n",
+    "#Calculation\n",
+    "a=d*math.sqrt(h**2+k**2+l**2);     #length(m)\n",
+    "V=a**3;       #volume of unit cell(m**3)\n",
+    "r=math.sqrt(3)*a/4;     #radius of atom(m)\n",
+    "\n",
+    "#Result\n",
+    "print \"length is\",round(a*10**9,3),\"*10**-9 m\"\n",
+    "print \"volume of unit cell is\",round(V*10**27,5),\"*10**-27 m**3\"\n",
+    "print \"answer for volume given in the book varies due to rounding off errors\"\n",
+    "print \"radius of atom is\",round(r*10**9,4),\"*10**-9 m\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example number 8, Page number 3-22"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 27,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "maximum order of diffraction is 2\n"
+     ]
+    }
+   ],
+   "source": [
+    "#importing modules\n",
+    "import math\n",
+    "from __future__ import division\n",
+    "\n",
+    "#Variable declaration\n",
+    "d=1.6;       #lattice spacing(angstrom)\n",
+    "theta=90*math.pi/180;     #glancing angle(radian)\n",
+    "lamda=1.5;    #wavelength of X-rays(angstrom)\n",
+    "\n",
+    "#Calculation\n",
+    "n=2*d*math.sin(theta)/lamda;       #maximum order of diffraction \n",
+    "\n",
+    "#Result\n",
+    "print \"maximum order of diffraction is\",int(n)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example number 9, Page number 3-23"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 34,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "glancing angle is 20 degrees 42 minutes 17 seconds\n",
+      "answer in the book is wrong\n"
+     ]
+    }
+   ],
+   "source": [
+    "#importing modules\n",
+    "import math\n",
+    "from __future__ import division\n",
+    "\n",
+    "#Variable declaration\n",
+    "a=0.26;         #lattice spacing(nm)\n",
+    "lamda=0.065;    #wavelength of X-rays(nm)\n",
+    "h=1;\n",
+    "k=1;\n",
+    "l=0;\n",
+    "n=2;\n",
+    "\n",
+    "#Calculation\n",
+    "d=a/math.sqrt(h**2+k**2+l**2);           \n",
+    "sintheta=n*lamda/(2*d);\n",
+    "theta=math.asin(sintheta)*180/math.pi;           #glancing angle(degrees)\n",
+    "thetad=int(theta);                               #glancing angle(degrees)  \n",
+    "thetam=(theta-thetad)*60;                        #glancing angle(minutes)\n",
+    "thetas=60*(thetam-int(thetam));                  #glancing angle(seconds)\n",
+    "\n",
+    "#Result\n",
+    "print \"glancing angle is\",thetad,\"degrees\",int(thetam),\"minutes\",int(thetas),\"seconds\"\n",
+    "print \"answer in the book is wrong\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example number 10, Page number 3-23"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 36,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "cube edge of unit cell is 4.055 angstrom\n"
+     ]
+    }
+   ],
+   "source": [
+    "#importing modules\n",
+    "import math\n",
+    "from __future__ import division\n",
+    "\n",
+    "#Variable declaration\n",
+    "n=1;     #order\n",
+    "theta=19.2*math.pi/180;     #glancing angle(radian)\n",
+    "lamda=1.54;                 #wavelength(angstrom)\n",
+    "h=1;\n",
+    "k=1;\n",
+    "l=1;\n",
+    "\n",
+    "#Calculation\n",
+    "d=n*lamda/(2*math.sin(theta));       #lattice parameter(angstrom)\n",
+    "a=d*math.sqrt(h**2+k**2+l**2);       #cube edge of unit cell(angstrom)\n",
+    "\n",
+    "#Result\n",
+    "print \"cube edge of unit cell is\",round(a,3),\"angstrom\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example number 11, Page number 3-24"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 42,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "lattice parameter is 3.522 angstrom\n"
+     ]
+    }
+   ],
+   "source": [
+    "#importing modules\n",
+    "import math\n",
+    "from __future__ import division\n",
+    "\n",
+    "#Variable declaration\n",
+    "n=1;     #order\n",
+    "theta=38.2*math.pi/180;     #glancing angle(radian)\n",
+    "lamda=1.54;                 #wavelength(angstrom)\n",
+    "h=2;\n",
+    "k=2;\n",
+    "l=0;\n",
+    "\n",
+    "#Calculation\n",
+    "d=n*lamda/(2*math.sin(theta));       #lattice parameter(angstrom)\n",
+    "a=d*math.sqrt(h**2+k**2+l**2);       #lattice parameter(angstrom)\n",
+    "\n",
+    "#Result\n",
+    "print \"lattice parameter is\",round(a,3),\"angstrom\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example number 12, Page number 3-24"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 43,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "interplanar spacing for (111) is 0.208 nm\n",
+      "interplanar spacing for (321) is 0.096 nm\n"
+     ]
+    }
+   ],
+   "source": [
+    "#importing modules\n",
+    "import math\n",
+    "from __future__ import division\n",
+    "\n",
+    "#Variable declaration\n",
+    "a=0.36;       #cube edge of unit cell(nm)\n",
+    "h1=1;\n",
+    "k1=1;\n",
+    "l1=1;\n",
+    "h2=3;\n",
+    "k2=2;\n",
+    "l2=1;\n",
+    "\n",
+    "#Calculation\n",
+    "d1=a/math.sqrt(h1**2+k1**2+l1**2);       #interplanar spacing for (111)(nm)\n",
+    "d2=a/math.sqrt(h2**2+k2**2+l2**2);       #interplanar spacing for (321)(nm)\n",
+    "\n",
+    "#Result\n",
+    "print \"interplanar spacing for (111) is\",round(d1,3),\"nm\"\n",
+    "print \"interplanar spacing for (321) is\",round(d2,3),\"nm\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example number 13, Page number 3-25"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 50,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "lattice spacing is 3.575 angstrom\n",
+      "glancing angle for 3rd order is 16 degrees 27.1 minutes\n",
+      "answer for minutes given in the book varies due to rounding off errors\n"
+     ]
+    }
+   ],
+   "source": [
+    "#importing modules\n",
+    "import math\n",
+    "from __future__ import division\n",
+    "\n",
+    "#Variable declaration\n",
+    "theta=(5+(25/60))*math.pi/180;     #glancing angle(radian)\n",
+    "lamda=0.675;   #wavelength of X-rays(angstrom)\n",
+    "n1=1;                  #order\n",
+    "n3=3;                  #order \n",
+    "\n",
+    "#Calculation\n",
+    "d=n1*lamda/(2*math.sin(theta));       #lattice spacing(angstrom)\n",
+    "d=round(d,3);\n",
+    "theta3=math.asin(n3*lamda/(2*d))*180/math.pi;    #glancing angle for 3rd order(degrees)\n",
+    "theta3d=int(theta3);                             #glancing angle for 3rd order(degrees)  \n",
+    "theta3m=(theta3-theta3d)*60;                     #glancing angle for 3rd order(minutes)\n",
+    "\n",
+    "#Result\n",
+    "print \"lattice spacing is\",d,\"angstrom\"\n",
+    "print \"glancing angle for 3rd order is\",theta3d,\"degrees\",round(theta3m,1),\"minutes\"\n",
+    "print \"answer for minutes given in the book varies due to rounding off errors\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example number 14, Page number 3-25"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 60,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "glancing angle is 23 degrees 56 minutes 31 seconds\n",
+      "answer given in the book is wrong\n"
+     ]
+    }
+   ],
+   "source": [
+    "#importing modules\n",
+    "import math\n",
+    "from __future__ import division\n",
+    "\n",
+    "#Variable declaration\n",
+    "d=3.04;         #interplanar spacing(angstrom)             \n",
+    "lamda=0.79;    #wavelength of X-rays(angstrom)\n",
+    "n=3;\n",
+    "\n",
+    "#Calculation\n",
+    "sintheta=n*lamda/(2*d);\n",
+    "thetad=math.asin(sintheta)*180/math.pi;           #glancing angle(degrees)\n",
+    "thetam=(theta-int(theta))*60;                        #glancing angle(minutes)\n",
+    "thetas=60*(thetam-int(thetam));                  #glancing angle(seconds)\n",
+    "\n",
+    "#Result\n",
+    "print \"glancing angle is\",int(round(thetad)),\"degrees\",int(thetam),\"minutes\",int(thetas),\"seconds\"\n",
+    "print \"answer given in the book is wrong\""
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 2",
+   "language": "python",
+   "name": "python2"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 2
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython2",
+   "version": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/sample_notebooks/SandhyaArroju/Chapter7.ipynb b/sample_notebooks/SandhyaArroju/Chapter7.ipynb
index 73c69a71..73c69a71 100644..100755
--- a/sample_notebooks/SandhyaArroju/Chapter7.ipynb
+++ b/sample_notebooks/SandhyaArroju/Chapter7.ipynb
diff --git a/sample_notebooks/asmitaasmita/1_An_overview_of_C++_2.ipynb b/sample_notebooks/asmitaasmita/1_An_overview_of_C++_2.ipynb
index ecf52ddd..ecf52ddd 100644..100755
--- a/sample_notebooks/asmitaasmita/1_An_overview_of_C++_2.ipynb
+++ b/sample_notebooks/asmitaasmita/1_An_overview_of_C++_2.ipynb