<!DOCTYPE OMNotebook>
<Notebook>
 <GroupCell closed="false" >
  <GroupCell closed="false" >
   <TextCell style="Title" >
    <Text>&lt;html>&lt;head>&lt;meta name="qrichtext" content="1" />&lt;/head>&lt;body style=" white-space: pre-wrap; font-family:MS Shell Dlg; font-size:8.25pt; font-weight:400; font-style:normal; text-decoration:none;">&lt;p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; font-family:Arial; font-size:38pt; font-weight:600; color:#000000;">if-Statements&lt;/p>&lt;/body>&lt;/html></Text>
   </TextCell>
   <GroupCell closed="false" >
    <TextCell style="Section" >
     <Text>&lt;html>&lt;head>&lt;meta name="qrichtext" content="1" />&lt;/head>&lt;body style=" white-space: pre-wrap; font-family:MS Shell Dlg; font-size:8.25pt; font-weight:400; font-style:normal; text-decoration:none;">&lt;p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; font-family:Times; font-size:18pt; font-weight:600; color:#000000;">General Description&lt;/p>&lt;/body>&lt;/html></Text>
    </TextCell>
    <TextCell style="Text" >
     <Text>&lt;html>&lt;head>&lt;meta name="qrichtext" content="1" />&lt;/head>&lt;body style=" white-space: pre-wrap; font-family:MS Shell Dlg; font-size:8.25pt; font-weight:400; font-style:normal; text-decoration:none;">&lt;p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; font-family:Times New Roman; font-size:12pt; color:#000000;">The semantics of an &lt;span style=" font-family:Courier New;">if&lt;/span>-statement is:&lt;/p>&lt;/body>&lt;/html></Text>
    </TextCell>
    <TextCell style="" >
     <Text>&lt;html>&lt;head>&lt;meta name="qrichtext" content="1" />&lt;/head>&lt;body style=" white-space: pre-wrap; font-family:MS Shell Dlg; font-size:8.25pt; font-weight:400; font-style:normal; text-decoration:none;">&lt;p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; font-size:8pt;">&lt;span style=" font-family:Times New Roman; font-size:12pt; color:#000000;">if the condition after the keyword if evaluates to true, the statements after &lt;/span>&lt;span style=" font-family:Courier New; font-size:12pt; color:#000000;">then&lt;/span>&lt;span style=" font-family:Times New Roman; font-size:12pt; color:#000000;"> are executed.&lt;/span>&lt;/p>&lt;/body>&lt;/html></Text>
    </TextCell>
    <TextCell style="" >
     <Text>&lt;html>&lt;head>&lt;meta name="qrichtext" content="1" />&lt;/head>&lt;body style=" white-space: pre-wrap; font-family:MS Shell Dlg; font-size:8.25pt; font-weight:400; font-style:normal; text-decoration:none;">&lt;p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; font-size:8pt;">&lt;span style=" font-family:Times New Roman; font-size:12pt; color:#000000;">Otherwise if there are one or more &lt;/span>&lt;span style=" font-family:Courier New; font-size:12pt; color:#000000;">elseif&lt;/span>&lt;span style=" font-family:Times New Roman; font-size:12pt; color:#000000;">-parts there conditions are evaluated in order; the first that evaluates to true causes the corresponding statements to be executed.&lt;/span>&lt;/p>&lt;/body>&lt;/html></Text>
    </TextCell>
    <TextCell style="" >
     <Text>&lt;html>&lt;head>&lt;meta name="qrichtext" content="1" />&lt;/head>&lt;body style=" white-space: pre-wrap; font-family:MS Shell Dlg; font-size:8.25pt; font-weight:400; font-style:normal; text-decoration:none;">&lt;p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; font-size:8pt;">&lt;span style=" font-family:Times New Roman; font-size:12pt; color:#000000;">Otherwise, if present, the statements in the &lt;/span>&lt;span style=" font-family:Courier New; font-size:12pt; color:#000000;">else&lt;/span>&lt;span style=" font-family:Times New Roman; font-size:12pt; color:#000000;">-part are executed.&lt;/span>&lt;/p>&lt;/body>&lt;/html></Text>
    </TextCell>
   </GroupCell>
   <GroupCell closed="false" >
    <TextCell style="Section" >
     <Text>&lt;html>&lt;head>&lt;meta name="qrichtext" content="1" />&lt;/head>&lt;body style=" white-space: pre-wrap; font-family:MS Shell Dlg; font-size:8.25pt; font-weight:400; font-style:normal; text-decoration:none;">&lt;p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; font-family:Times; font-size:18pt; font-weight:600; color:#000000;">SumVector&lt;/p>&lt;/body>&lt;/html></Text>
    </TextCell>
    <TextCell style="Text" >
     <Text>&lt;html>&lt;head>&lt;meta name="qrichtext" content="1" />&lt;/head>&lt;body style=" white-space: pre-wrap; font-family:MS Shell Dlg; font-size:8.25pt; font-weight:400; font-style:normal; text-decoration:none;">&lt;p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; font-family:Times New Roman; font-size:12pt; color:#000000;">In the class SumVector there is an exmple of an &lt;span style=" font-family:Courier New;">if&lt;/span>-statement which performs a combined summation and computation on a vector v.&lt;/p>&lt;/body>&lt;/html></Text>
    </TextCell>
    <InputCell style="Input" closed="true" >
     <Input>class SumVector
  Real sum;
  parameter Real v[5] = {100, 200, -300, 400, 500};
  parameter Integer n = size(v, 1);
algorithm
  sum := 0;
  for i in 1:n loop
    if v[i] > 0 then
      sum := sum + v[i];
    elseif v[i] > -1 then
      sum := sum + v[i] - 1;
    else
      sum := sum - v[i];      
    end if;
  end for;
end SumVector;      
</Input>
     <Output></Output>
    </InputCell>
   </GroupCell>
   <GroupCell closed="false" >
    <TextCell style="Section" >
     <Text>&lt;html>&lt;head>&lt;meta name="qrichtext" content="1" />&lt;/head>&lt;body style=" white-space: pre-wrap; font-family:MS Shell Dlg; font-size:8.25pt; font-weight:400; font-style:normal; text-decoration:none;">&lt;p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; font-family:Times; font-size:18pt; font-weight:600; color:#000000;">Simulation of SumVector&lt;/p>&lt;/body>&lt;/html></Text>
    </TextCell>
    <TextCell style="Text" >
     <Text>&lt;html>&lt;head>&lt;meta name="qrichtext" content="1" />&lt;/head>&lt;body style=" white-space: pre-wrap; font-family:MS Shell Dlg; font-size:8.25pt; font-weight:400; font-style:normal; text-decoration:none;">&lt;p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; font-family:Times New Roman; font-size:12pt; color:#000000;">After we have simulated &lt;span style=" font-family:Courier New;">SumVector&lt;/span> we see that the sum of the absolute value of the elements in the vecor is 1500.&lt;/p>&lt;/body>&lt;/html></Text>
    </TextCell>
    <InputCell style="Input" closed="true" >
     <Input>simulate( SumVector );</Input>
     <Output></Output>
    </InputCell>
    <TextCell style="Output" >
     <Text>&lt;html>&lt;head>&lt;meta name="qrichtext" content="1" />&lt;/head>&lt;body style=" white-space: pre-wrap; font-family:MS Shell Dlg; font-size:8.25pt; font-weight:400; font-style:normal; text-decoration:none;">&lt;p style="-qt-paragraph-type:empty; margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; font-family:Courier New; font-size:11pt; color:#000000;">&lt;/p>&lt;/body>&lt;/html></Text>
    </TextCell>
    <InputCell style="Input" closed="true" >
     <Input>sum[0]
</Input>
     <Output></Output>
    </InputCell>
   </GroupCell>
   <GroupCell closed="false" >
    <TextCell style="Section" >
     <Text>&lt;html>&lt;head>&lt;meta name="qrichtext" content="1" />&lt;/head>&lt;body style=" white-space: pre-wrap; font-family:MS Shell Dlg; font-size:8.25pt; font-weight:400; font-style:normal; text-decoration:none;">&lt;p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; font-family:Times; font-size:18pt; font-weight:600; color:#000000;">Assignments within if-Statements&lt;/p>&lt;/body>&lt;/html></Text>
    </TextCell>
    <TextCell style="Text" >
     <Text>&lt;html>&lt;head>&lt;meta name="qrichtext" content="1" />&lt;/head>&lt;body style=" white-space: pre-wrap; font-family:MS Shell Dlg; font-size:8.25pt; font-weight:400; font-style:normal; text-decoration:none;">&lt;p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; font-family:Times New Roman; font-size:12pt; color:#000000;">There are a special feature regarding assignment statements inside &lt;span style=" font-family:Courier New;">if&lt;/span>-statements. Modelica guarantees that all the outputs of an algorithm section always have well-defined values, and that an algorithm section does &lt;span style=" font-style:italic;">not&lt;/span> have memory of previous invocations. This is achieved by &lt;span style=" font-style:italic;">initializing&lt;/span> all &lt;span style=" font-style:italic;">conditionally assigned variables&lt;/span> to their start-values whenever the algorithm is invoked. &lt;/p>&lt;/body>&lt;/html></Text>
    </TextCell>
    <GroupCell closed="false" >
     <TextCell style="Subsection" >
      <Text>&lt;html>&lt;head>&lt;meta name="qrichtext" content="1" />&lt;/head>&lt;body style=" white-space: pre-wrap; font-family:MS Shell Dlg; font-size:8.25pt; font-weight:400; font-style:normal; text-decoration:none;">&lt;p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; font-family:Times; font-size:14pt; font-weight:600; color:#000000;">CondAssign&lt;/p>&lt;/body>&lt;/html></Text>
     </TextCell>
     <TextCell style="Text" >
      <Text>&lt;html>&lt;head>&lt;meta name="qrichtext" content="1" />&lt;/head>&lt;body style=" white-space: pre-wrap; font-family:MS Shell Dlg; font-size:8.25pt; font-weight:400; font-style:normal; text-decoration:none;">&lt;p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; font-family:Times New Roman; font-size:12pt; color:#000000;">The algorithm section in the class &lt;span style=" font-family:Courier New;">CondAssign&lt;/span> below automatically assigns the start values 35 and 45 to the variables &lt;span style=" font-family:Courier New;">x&lt;/span> and &lt;span style=" font-family:Courier New;">y&lt;/span> respectively when entering the algorithm section since these variables are conditionally assigned within the algorithm section. This means that the condition &lt;span style=" font-family:Courier New;">x&amp;gt;5 &lt;/span>becomes &lt;span style=" font-family:Courier New;">35&amp;gt;5&lt;/span> which is always true. On the other hand, the variable z is not given its start value when entering the algorithm section since it is not conditionally assigned; it is actually an input to the algorithm section.&lt;br />&lt;/p>&lt;/body>&lt;/html></Text>
     </TextCell>
     <InputCell style="Input" closed="true" >
      <Input>class CondAssign
  Real x(start = 35);
  Real y(start = 45);
  parameter Real z := 0;
algorithm
  if x > 5 then 
    x := 400;      
  end if;  
  if z > 10 then 
    y := 500;    
  end if;  
end CondAssign;  
</Input>
      <Output></Output>
     </InputCell>
    </GroupCell>
    <GroupCell closed="false" >
     <TextCell style="Subsection" >
      <Text>&lt;html>&lt;head>&lt;meta name="qrichtext" content="1" />&lt;/head>&lt;body style=" white-space: pre-wrap; font-family:MS Shell Dlg; font-size:8.25pt; font-weight:400; font-style:normal; text-decoration:none;">&lt;p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; font-family:Times; font-size:14pt; font-weight:600; color:#000000;">Simulation of CondAssign&lt;/p>&lt;/body>&lt;/html></Text>
     </TextCell>
     <InputCell style="Input" closed="true" >
      <Input>simulate( CondAssign );</Input>
      <Output></Output>
     </InputCell>
     <TextCell style="Output" >
      <Text>&lt;html>&lt;head>&lt;meta name="qrichtext" content="1" />&lt;/head>&lt;body style=" white-space: pre-wrap; font-family:MS Shell Dlg; font-size:8.25pt; font-weight:400; font-style:normal; text-decoration:none;">&lt;p style="-qt-paragraph-type:empty; margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; font-family:Courier New; font-size:11pt; color:#000000;">&lt;/p>&lt;/body>&lt;/html></Text>
     </TextCell>
    </GroupCell>
    <GroupCell closed="false" >
     <TextCell style="Subsection" >
      <Text>&lt;html>&lt;head>&lt;meta name="qrichtext" content="1" />&lt;/head>&lt;body style=" white-space: pre-wrap; font-family:MS Shell Dlg; font-size:8.25pt; font-weight:400; font-style:normal; text-decoration:none;">&lt;p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; font-family:Times; font-size:14pt; font-weight:600; color:#000000;">CondAssign&lt;/p>&lt;/body>&lt;/html></Text>
     </TextCell>
     <TextCell style="Text" >
      <Text>&lt;html>&lt;head>&lt;meta name="qrichtext" content="1" />&lt;/head>&lt;body style=" white-space: pre-wrap; font-family:MS Shell Dlg; font-size:8.25pt; font-weight:400; font-style:normal; text-decoration:none;">&lt;p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; font-family:Times New Roman; font-size:12pt; color:#000000;">The function CondAssignFunc below behaves similarily. Here the local variables x and y are automatically assigned the default initial values 35 and 45 on entry to the algorithm section that comprises its function body.&lt;br />&lt;/p>&lt;/body>&lt;/html></Text>
     </TextCell>
     <InputCell style="Input" closed="true" >
      <Input>function CondAssignFunc
  input Real z;
  output Real x := 35;
  output Real y := 45;
algorithm
  if x > 5 then
    x := 400;
  end if;
  if z > 10 then
    y := 500;
  end if;
end CondAssignFunc;          
</Input>
      <Output></Output>
     </InputCell>
     <TextCell style="Text" >
      <Text>&lt;html>&lt;head>&lt;meta name="qrichtext" content="1" />&lt;/head>&lt;body style=" white-space: pre-wrap; font-family:MS Shell Dlg; font-size:8.25pt; font-weight:400; font-style:normal; text-decoration:none;">&lt;p style="-qt-paragraph-type:empty; margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; font-family:Times New Roman; font-size:12pt; color:#000000;">&lt;/p>&lt;/body>&lt;/html></Text>
     </TextCell>
     <InputCell style="Input" closed="true" >
      <Input>class CondAssignFuncCall
  Real a, b;
equation
  (a, b) = CondAssignFunc(z = 5);
end CondAssignFuncCall;</Input>
      <Output></Output>
     </InputCell>
    </GroupCell>
    <GroupCell closed="false" >
     <TextCell style="Subsection" >
      <Text>&lt;html>&lt;head>&lt;meta name="qrichtext" content="1" />&lt;/head>&lt;body style=" white-space: pre-wrap; font-family:MS Shell Dlg; font-size:8.25pt; font-weight:400; font-style:normal; text-decoration:none;">&lt;p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; font-family:Times; font-size:14pt; font-weight:600; color:#000000;">Simulation of CondAssignFuncCall&lt;/p>&lt;/body>&lt;/html></Text>
     </TextCell>
     <InputCell style="Input" closed="true" >
      <Input>simulate( CondAssignFuncCall );</Input>
      <Output></Output>
     </InputCell>
     <TextCell style="Output" >
      <Text>&lt;html>&lt;head>&lt;meta name="qrichtext" content="1" />&lt;/head>&lt;body style=" white-space: pre-wrap; font-family:MS Shell Dlg; font-size:8.25pt; font-weight:400; font-style:normal; text-decoration:none;">&lt;p style="-qt-paragraph-type:empty; margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; font-family:Courier New; font-size:11pt; color:#000000;">&lt;/p>&lt;/body>&lt;/html></Text>
     </TextCell>
     <InputCell style="Input" closed="true" >
      <Input>{a[0]
, b[0]

}
</Input>
      <Output></Output>
     </InputCell>
    </GroupCell>
   </GroupCell>
  </GroupCell>
 </GroupCell>
</Notebook>
