## Buildings.Fluid.Utilities.BaseClasses

Package with base classes for Buildings.Fluid.Utilities

### Information

This package contains base classes that are used to construct the models in Buildings.Fluid.Utilities.

Extends from Modelica.Icons.BasesPackage (Icon for packages containing base classes).

### Package Content

NameDescription
der_extendedPolynomial Polynomial that is linearly extended at user specified values

## Buildings.Fluid.Utilities.BaseClasses.der_extendedPolynomial

Polynomial that is linearly extended at user specified values

### Information

This function is the derivative of extendedPolynomial with respect to `x`.

Extends from Modelica.Icons.Function (Icon for functions).

### Inputs

TypeNameDefaultDescription
Realx x value
Realc[:] Polynomial coefficients
RealxMin Minimum x value for polynomial
RealxMax Maximum x value for polynomial
Realder_x

### Outputs

TypeNameDescription
Realder_yDerivative dy/dx

### Modelica definition

```function der_extendedPolynomial
"Polynomial that is linearly extended at user specified values"
extends Modelica.Icons.Function;
input Real x "x value";
input Real[:] c "Polynomial coefficients";
input Real xMin "Minimum x value for polynomial";
input Real xMax "Maximum x value for polynomial";
input Real der_x;
output Real der_y "Derivative dy/dx";
protected
Integer N = size(c,1) "Number of coefficients";
algorithm
if x < xMin then
der_y := 0;
for i in 2:N loop
der_y := der_y + (i - 1)*xMin^(i - 2)*c[i];
end for;
elseif x < xMax then
der_y := 0;
for i in 2:N loop
der_y := der_y + (i - 1)*x^(i - 2)*c[i];
end for;
else
der_y := 0;
for i in 2:N loop
der_y := der_y + (i - 1)*xMax^(i - 2)*c[i];
end for;
end if;
end der_extendedPolynomial;
```

Automatically generated Wed Feb 29 16:53:32 2012.