Page 13 - Excel for Scientists and Engineers: Numerical Methods

X EXCEL: NUMERICAL METHODS

Chapter 5 Interpolation 77
Obtaining Values from a Table ............................................................................ 77
Using Excel's Lookup Functions to Obtain Values from a Table .................. 77
Using VLOOKUP to Obtain Values from a Table .......................................... 78
Using the LOOKUP Function to Obtain Values from a Table ....................... 79
Creating a Custom Lookup Formula to Obtain Values from a Table ............ 80
Using Excel's Lookup Functions
to Obtain Values from a Two-way Table .................................................. 81
Interpolation ......................................................................................................... 83
Linear Interpolation in a Table by Means of Worksheet Formulas ............... 83
Linear Interpolation in a Table by Using the TREND Worksheet Function .. 85
Linear Interpolation in a Table by Means of a Custom Function .................. 86
Cubic Interpolation ........................................................................................ 87
Cubic Interpolation in a Table by Using the TREND Worksheet Function ... 89
Linear Interpolation in a Two-way Table
by Means of Worksheet Formulas .............................................................. 90
Cubic Interpolation in a Two-way Table
by Means of Worksheet Formulas .............................................................. 91
Cubic Interpolation in a Two-way Table
by Means of a Custom Function ................................................................. 93
Problems ............................................................................................................... 96
Chapter 6 Differentiation 99
First and Second Derivatives of Data in a Table .................................................. 99
Calculating First and Second Derivatives .......................................................... 100
Using LINEST as a Fitting Function ............................................................ 105
Derivatives of a Worksheet Formula .................................................................. 109
Derivatives of a Worksheet Formula Calculated by Using
a VBA Function Procedure ...................................................................... 109
First Derivative of a Worksheet Formula Calculated by Using
the Finite-Difference Method ................................................................... 110
The Newton Quotient ................................................................................... 110
Derivative of a Worksheet Formula Calculated by Using
the Finite-Difference Method ................................................................... 111
First Derivative of a Worksheet Formula Calculated by Using
a VBA Sub Procedure Using the Finite-Difference Method .................... 112
First Derivative of a Worksheet Formula Calculated by Using
a VBA Function Procedure Using the Finite-Difference Method ............ 115
Improving the VBA Function Procedure ..................................................... 118
Second Derivative of a Worksheet Formula ................................................ 120
Concerning the Choice of Ax for the Finite-Difference Method ................. 123
Problems ............................................................................................................. 124