# ExceLab 365 Calculus Functions Add-in

## by ExcelWorks LLC

## Solve calculus integrals, derivatives, equations, and interpolation problems with simple formulas.

This cross-platform unique Add-in from ExcelWorks extends Excel with a super set of powerful calculus functions which you use in standard formulas just like native functions to solve various calculus problems. For example, to integrate a formula stored in `A1` with respect to `X1` between 1 and 2, you use the `QUADF` function in a formula just like this: `=QUADF(A1,X1,1,2)`

. In fact, to integrate a simple formula, you can pass it directly like this: `=QUADF(X1*SQRT(X1), X1,1,2)`

.

Likewise, to solve coupled equations defined by formulas in `Y1, Y2` and `Y3` with respect to the variables `X1, X2` and `X3`, you use the `NLSOLVE` function in a formula just like this: `=NLSOLVE(Y1:Y3,X1:X3)`

.

It is that simple! But have no doubts, these all-new calculus functions pack state of the art proven algorithms with potent performance and precision. They have been granted four US Patents and are being utilized since 2015 around the Globe. By installing this Add-in, you will be able to solve a variety of calculus problems including:

- Computing single and multiple integrals of any order (with finite and infinite limits).
- Computing first and higher order derivatives of functions.
- Computing integrals and derivatives of discrete
`(x,y)`data points by aid of splines. - Interpolating and gridding scattered 2D and 3D data points.
- Solving nonlinear equations and inequalities.
- Solving least-square curve fitting problems.
- Solving ODE and DAE initial and boundary value problems.
- Solving PDE problems.
- Solving parametric optimization problems.

In fact, you can combine the calculus functions to solve very complex parametric optimization problems with remarkable ease. The Add-in also packs very powerful 2D and 3D interpolation functions based on splines and natural neighbor algorithms. For example, with GRIDXYZ you can easily interpolate scattered (x,y,z) data points onto a uniform rectilinear grid for easy surface plotting in Excel.

No skills are required to use the calculus functions beyond basic familiarity with Excel spreadsheet concepts and rules. The detailed help pages for each function contain several examples to get you started. If you are using Excel on a PC running MS Windows OS., then consider installing the desktop version ExceLab 7.0 available for download from excel-works.com. ExceLab 7.0 packs additional powerful ODE/PDE solver functions and direct coupling to Excel engine which eliminates internet induced variabilities in performance.

Upon installing the add-in, you are automatically granted a free evaluation license. You can renew or check the status of your license directly from Excel Ribbon by clicking Formulas → Calculus Functions → Account.

### Add-in capabilities

- Can read and make changes to your document
- Can send data over the Internet