## Facemorph.Stats Class Functions

```java.lang.Object
Facemorph.Stats.Functions
```

`public class Functionsextends java.lang.Object`

A set of static statistical funtcions

Nested Class Summary
`static class` `Functions.StatisticsException`

Constructor Summary
`Functions()`

Method Summary
`static double` ```dotProduct(double[] left, double[] right)```
Return the inner (dot) product for two vectors
`static double` `magnitude(double[] vec)`

`static void` `main(java.lang.String[] args)`

`static double[]` ```multiply(double[] vec, double scalar)```

`static void` ```multiplyInPlace(double[] vec, double scalar)```

`static void` ```multiplyInPlace(double[] vec, double[] vec2)```

`static double[]` `normalize(double[] vec)`

`static void` `normalizeInPlace(double[] vec)`

`static double` ```rSqr(double[] y, double[] yhat)```
Calcuate the R^2 (coefficient of determination) for an estimator
`static double[]` ```scale(double[] v, double s)```

`static void` ```scaleInPlace(double[] v, double s)```

`static double[]` ```subtract(double[] lhs, double rhs)```

`static double[]` ```subtract(double[] lhs, double[] rhs)```

`static double` ```SumSquaredResiduals(double[] y, double[] yhat)```
Calculate the sum of squared residuals between predicted and actual values

Methods inherited from class java.lang.Object
`clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

Constructor Detail

### Functions

`public Functions()`
Method Detail

### rSqr

```public static double rSqr(double[] y,
double[] yhat)```
Calcuate the R^2 (coefficient of determination) for an estimator

Parameters:
`y` - the original values of the variable
`yhat` - the estimated values of the variable by some measure
Returns:

### SumSquaredResiduals

```public static double SumSquaredResiduals(double[] y,
double[] yhat)```
Calculate the sum of squared residuals between predicted and actual values

Parameters:
`y` - the original values of the dependent
`yhat` - the estimated values by the regression
Returns:
sum of squared residuals

### dotProduct

```public static double dotProduct(double[] left,
double[] right)```
Return the inner (dot) product for two vectors

Parameters:
`left` - first vector
`right` - second vector
Returns:
inner product
Throws:
`BigMatException` - if the two vectors are no the same length

### scale

```public static double[] scale(double[] v,
double s)```

### scaleInPlace

```public static void scaleInPlace(double[] v,
double s)```

### normalize

`public static double[] normalize(double[] vec)`

### normalizeInPlace

`public static void normalizeInPlace(double[] vec)`

### subtract

```public static double[] subtract(double[] lhs,
double[] rhs)```

### subtract

```public static double[] subtract(double[] lhs,
double rhs)```

### magnitude

`public static double magnitude(double[] vec)`

### multiplyInPlace

```public static void multiplyInPlace(double[] vec,
double[] vec2)```

### multiplyInPlace

```public static void multiplyInPlace(double[] vec,
double scalar)```

### multiply

```public static double[] multiply(double[] vec,
double scalar)```

### main

`public static void main(java.lang.String[] args)`