Java Reference

Java Reference

ConstantExpression.java
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13 
14 package com.google.ortools.sat;
15 
17 public final class ConstantExpression implements LinearExpr {
18  private final long offset;
19 
20  public ConstantExpression(long offset) {
21  this.offset = offset;
22  }
23 
24  // LinearArgument interface.
25  @Override
26  public LinearExpr build() {
27  return this;
28  }
29 
30  // LinearExpr interface.
31  @Override
32  public int numElements() {
33  return 0;
34  }
35 
36  @Override
37  public int getVariableIndex(int index) {
38  throw new IllegalArgumentException("wrong index in LinearExpr.getVariable(): " + index);
39  }
40 
41  @Override
42  public long getCoefficient(int index) {
43  throw new IllegalArgumentException("wrong index in LinearExpr.getCoefficient(): " + index);
44  }
45 
46  @Override
47  public long getOffset() {
48  return offset;
49  }
50 
51  @Override
52  public String toString() {
53  return String.format("%d", offset);
54  }
55 }
A linear expression (sum (ai * xi) + b).
Definition: LinearExpr.java:19
long getCoefficient(int index)
Returns the ith coefficient.
A specialized constant linear expression.
LinearExpr build()
Builds a linear expression.
long getOffset()
Returns the constant part of the expression.
int numElements()
Returns the number of terms (excluding the constant one) in this expression.
int getVariableIndex(int index)
Returns the index of the ith variable.