**vCalc's** Equation Editor and Constant Editor allow you to select from the library of **vCalc** equations, constants and data sets and to *drag-and-drop* these **tokens**^{1} into your equation's code or your constant's code. You can thus use anything that exists in **vCalc** to create something new and/or more powerful.

This page discusses some of the tokens that have been produced with the specific intent to be used as Equations-in-Equations (**EiEs**). These equations do something that might be used frequently in other equations or constants and used as **EiEs** they are time-saving devices. These **EiEs** are like a re-use library of simple standard functions built into **vCalc's** simple Groovy-based coding environment.

Some **EiEs**, created as function to be used like stored sub-routines, are very simple in nature. They do something so we don;t have to re-code that part of the code. They add a functionality to an equation by simply dragging them into another equation.

Other equations are complicated but still can be used as an **EiE**. Sometimes it's time saving to drag in a complex equation just to change that equations inputs.

Let's explore some **EiE** examples.

Contents

# Random numbers

Here are equations that generate random numbers and random selection in various forms:

- A RANDOM REAL FROM AN INPUT RANGE
- A RANDOM INTEGER FROM A RANGE
- A RANDOM SELECTION OF VALUES
- A RANDOM INTEGER BETWEEN 0 & YOUR CHOICE]
- A RANDOM REAL BETWEEN 0 & YOUR CHOICE
- A RANDOM REAL FROM 0.0 to 1.0
- A RANDOM 0 or 1
- A COIN FLIP
- A RANDOM ROLL OF DICE

# Statistics

- Minimum of a data set
- Maximum of a data set
- Range of a data set
- Mean of a data set
- Median of a data set
- Mode of a data set
- Standard deviation of a data set (population)
- Standard deviation of a data set (sample)
- Variance in a data set (population)
- Variance in a data set (sample)
- z-score of a element from a data set
- z-score from a known mean and SD
- Frequency distributions

# Matrix Functions

- Trace of a matrix
- Determinant of a matrix
- Inverse of a matrix
- Cramer's rule computation of simultaneous equations
- Scalar multiplication
- Minor of a matrix
- Eigenvalues of a matrix
- 3-Vector Norm
- 4-Vector Norm