如何使用Solver Foundation Services将“元素”设置为“约束”中的系数

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问题描述

给定一个Decision变量x，参数ABSCISSA和ORDINATE都有ABSCISSA.IndexSets.Count == ORDINATE.IndexSets.Count == 1，我试图建立一个近似于分段线性的SOS2约束由坐标
（ABSCISSA [i]，ORDINATE [i]）给出的实值函数，i在ABSCISSA.IndexSets [0]中。 ABSCISSA值保证按严格单调递增的顺序排序，但可能会包含值0.0。因此，ABSCISSA不能用于"参考行"。因为系数只允许非零值
。

Given a Decision variable x, and Parameter ABSCISSA and ORDINATE both of which have ABSCISSA.IndexSets.Count == ORDINATE.IndexSets.Count == 1, I am trying to set up a SOS2 constraint that approximates piecewise linear a real-valued function given by coordinates (ABSCISSA[i],ORDINATE[i]), i in ABSCISSA.IndexSets[0]. The ABSCISSA values are guaranteed to be sorted in strictly monotonically increasing order, but may contain the value 0.0. Hence ABSCISSA cannot be used in the "Reference-Row" as only non-zero values for the coefficients are allowed.

因此我编码：

决策sos_dummy =新决策（域名。 RealRange（0.0,1.0），" sos_dummy"）;
$
决定sos_x =新决策（Domain.Real，" sos_x"，ABSCISSA.IndexSets [0]）;

决定fx =新决策（Domain.Real，" fx"）;

model.AddDecisions（sos_dummy，sos_x，sos_fx）;

¥ b $ b //参考行

model.AddConstraint（" RefRowCnstr"，

    Model.Sos2（sos_dummy == Model.Sum（Model） .ForEach（ABSCISSA.IndexSets [0]，k =>
（k + 1） * sos_x [k]）））;

//横坐标行

model.AddConstraint（" AbscissaRowCnstr"，&
    x == Model.Sum（Model.ForEach）（ABSCISSA.IndexSets [0]，k => ABSCISSA [k] * sos_x [k]）））;
$

//纵坐标行

model.AddConstraint（" OrdinateRowCnstr"，

    fx == Mod el.Sum（Model.ForEach（ABSCISSA.IndexSets [0]，k => ORDINATE [k] * sos_x [k]）））;
$

//凸性行（不确定我是否需要它）

model.AddConstraint（" ConvexityRowCnstr"，&
    1.0 == Model.Sum（Model.ForEach（ABSCISSA.IndexSets [0]，k => sos_x [k] ）））;
$

术语objectiveTerm = fx;

Decision sos_dummy = new Decision(Domain.RealRange(0.0, 1.0), "sos_dummy");
Decision sos_x = new Decision(Domain.Real, "sos_x", ABSCISSA.IndexSets[0]);
Decision fx = new Decision(Domain.Real, "fx");
model.AddDecisions(sos_dummy, sos_x, sos_fx);

// Reference row
model.AddConstraint("RefRowCnstr",
    Model.Sos2(sos_dummy == Model.Sum(Model.ForEach(ABSCISSA.IndexSets[0], k =>(k+1) * sos_x[k])));

// Abscissa row
model.AddConstraint("AbscissaRowCnstr",
    x == Model.Sum(Model.ForEach(ABSCISSA.IndexSets[0], k => ABSCISSA[k] * sos_x[k])));

// Ordinate row
model.AddConstraint("OrdinateRowCnstr",
    fx == Model.Sum(Model.ForEach(ABSCISSA.IndexSets[0], k => ORDINATE[k] * sos_x[k])));

// Convexity row (not sure that I need that at all)
model.AddConstraint("ConvexityRowCnstr",
    1.0 == Model.Sum(Model.ForEach(ABSCISSA.IndexSets[0], k => sos_x[k])));

Term objectiveTerm = fx;

我遇到的问题是"参考行"和"参考行"。粗体位：索引
k 不能用作参考行中的系数。因此我想创建一个新变量

The problem I run into is with the "Reference-Row" bit in bold: The index k cannot not be used as the coefficient in the reference row. Hence I would like to create a new variable

参数INDEX = new Parameter（Domain.IntegerNonnegative，" INDEX"，ABSCISSA.IndexSets [0]）;

Parameter INDEX = new Parameter(Domain.IntegerNonnegative, "INDEX", ABSCISSA.IndexSets[0]);

然后我可以绑定到整数数组

which I then could bind to an Integer array

int [] index = new int [ABSCISSA.IndexSets [0] .Size]; //或Count或NumElements或其他

int[] index = new int[ABSCISSA.IndexSets[0].Size]; // or Count or NumElements or whatever

并将其初始化为

for（int i = 0; i< ABSCISSA.IndexSets [0] .Size; ++ i）

{

index [i] =（i + 1）;

}

for(int i = 0; i < ABSCISSA.IndexSets[0].Size; ++i)
{
index[i] = (i + 1);
}

INDEX.SetBinding（index）; &NBSP;&NBSP;&NBSP;&NBSP;&NBSP; //注意我有BindingUtilities可用，它将SetBinding扩展为int []和double []。

INDEX.SetBinding(index); // note I have the BindingUtilities available that extents the SetBinding to int[] and double[].

参考行将是：

//参考行

model.AddConstraint（" RefRowCnstr"，

Model.Sos2（sos_dummy == Model.Sum（Model.ForEach（ ABSCISSA.IndexSets [0]，k =>
INDEX [k] * sos_x [k]）））;

// Reference row
model.AddConstraint("RefRowCnstr",
Model.Sos2(sos_dummy == Model.Sum(Model.ForEach(ABSCISSA.IndexSets[0], k =>INDEX[k] * sos_x[k])));

代替。

Unfortunatley.Microsoft.SolverFoundation.Services.Set没有任何方法或属性可以获取给定集合中的元素数量。我怎么能实现这种行为？任何提示都表示赞赏。

Unfortunatley. Microsoft.SolverFoundation.Services.Set does not have any method or property that allows to get at the number of elements in a given set. How could I achieve this behaviour? Any hint appreciated.

ABSCISSA

如何使用Solver Foundation Services将“元素”设置为“约束”中的系数

问题描述

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