Buildings.Fluid.Utilities
Package with utility functions
Information
This package contains utility classes that are used by the package Buildings.Fluid.
Extends from Modelica.Icons.Package (Icon for standard packages).
Package Content
| Name | Description |
|---|---|
 extendedPolynomial
|
Polynomial that is linearly extended at user specified values |
| polynomial
|
Polynomial, used because OpenModelica 1.4.3 does not expand the sum() into a scalar |
 Examples
|
Collection of models that illustrate model use and test models |
 BaseClasses
|
Package with base classes for Buildings.Fluid.Utilities |
Buildings.Fluid.Utilities.extendedPolynomial
Polynomial that is linearly extended at user specified values
Information
For x between the bounds xmin < x < xmax, this function defines a polynomialy = ∑i=1n ci xi-1
where n > 1 and xmin, xmax are parameters. For x < xmin and x > xmax, the polynomial is replaced by a linear function in such a way that the first derivative is continuous everywhere.Extends from Modelica.Icons.Function (Icon for functions).
Inputs
| Type | Name | Default | Description |
|---|---|---|---|
| Real | x | x value | |
| Real | c[:] | Polynomial coefficients | |
| Real | xMin | Minimum x value for polynomial | |
| Real | xMax | Maximum x value for polynomial |
Outputs
| Type | Name | Description |
|---|---|---|
| Real | y | y value |
Modelica definition
function extendedPolynomial
"Polynomial that is linearly extended at user specified values"
annotation(derivative=BaseClasses.der_extendedPolynomial);
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";
output Real y "y value";
protected
Integer N = size(c,1) "Number of coefficients";
algorithm
if x < xMin then
y := c[1];
for i in 2:N loop
y := y + xMin^(i - 1)*c[i] + (x - xMin)*(i - 1)*xMin^(i - 2)*c[i];
end for;
elseif x < xMax then
y := c[1];
for i in 2:N loop
y := y + x^(i - 1)*c[i];
end for;
else
y := c[1];
for i in 2:N loop
y := y + xMax^(i - 1)*c[i] + (x - xMax)*(i - 1)*xMax^(i - 2)*c[i];
end for;
end if;
end extendedPolynomial;
Buildings.Fluid.Utilities.polynomial
Polynomial, used because OpenModelica 1.4.3 does not expand the sum() into a scalar
Information
Function that computes
y = ∑i=1n ci xi-1
Extends from Modelica.Icons.Function (Icon for functions).
Inputs
| Type | Name | Default | Description |
|---|---|---|---|
| Real | c[:] | Coefficients | |
| Real | x | Independent variable |
Outputs
| Type | Name | Description |
|---|---|---|
| Real | y | Dependent variable |
Modelica definition
function polynomial
"Polynomial, used because OpenModelica 1.4.3 does not expand the sum() into a scalar"
extends Modelica.Icons.Function;
input Real[:] c "Coefficients";
input Real x "Independent variable";
output Real y "Dependent variable";
algorithm
y := c[1];
for i in 2 : size(c,1) loop
y := y + x^(i-1) * c[i];
end for;
end polynomial;