/// <summary>
/// Gets colimit
/// </summary>
/// <param name="category">The category</param>
/// <param name="arrows">Diagram arrows</param>
/// <param name="coequalizer">Coequalizer</param>
/// <param name="objectArrows">Arrows to colimit</param>
/// <param name="productArrows">Sum arrows</param>
/// <returns>The colimit</returns>
public static IAdvancedCategoryObject GetColim(ICategory category, IList <IAdvancedCategoryArrow> arrows,
ref IAdvancedCategoryArrow coequalizer, ref IList <IAdvancedCategoryArrow> objectArrows, ref IList <IAdvancedCategoryArrow> productArrows)
{
IList <IAdvancedCategoryObject> objects = new List <IAdvancedCategoryObject>();
IList <IAdvancedCategoryObject> sources = new List <IAdvancedCategoryObject>();
IDirectSumCategory direct = category as IDirectSumCategory;
ICoequalizerCategory coequ = category as ICoequalizerCategory;
foreach (IAdvancedCategoryArrow arrow in arrows)
{
if (!objects.Contains(arrow.Source as IAdvancedCategoryObject))
{
objects.Add(arrow.Source as IAdvancedCategoryObject);
}
if (!objects.Contains(arrow.Target as IAdvancedCategoryObject))
{
objects.Add(arrow.Source as IAdvancedCategoryObject);
}
sources.Add(arrow.Source as IAdvancedCategoryObject);
}
IList <IAdvancedCategoryArrow> productSourceArrows = new List <IAdvancedCategoryArrow>();
productArrows = new List <IAdvancedCategoryArrow>();
IAdvancedCategoryObject product = direct.GetDirectSum(objects, productArrows);
IAdvancedCategoryObject productSource = direct.GetDirectSum(sources, productSourceArrows);
IList <IAdvancedCategoryArrow> coequList = new List <IAdvancedCategoryArrow>();
IList <IAdvancedCategoryArrow> arrList = new List <IAdvancedCategoryArrow>();
foreach (IAdvancedCategoryArrow arr in productArrows)
{
IAdvancedCategoryObject target = arr.Target as IAdvancedCategoryObject;
foreach (IAdvancedCategoryObject t in sources)
{
if (t == target)
{
arrList.Add(arr);
}
}
}
IAdvancedCategoryArrow first = direct.GetArrowFromDirectSum(product, productSource, arrList);
foreach (IAdvancedCategoryArrow arr in arrows)
{
int num = objects.IndexOf(arr.Target as IAdvancedCategoryObject);
IAdvancedCategoryArrow pr = productArrows[num] as IAdvancedCategoryArrow;
IAdvancedCategoryArrow eq = pr.Compose(category, arr);
coequList.Add(eq);
}
IAdvancedCategoryArrow second = direct.GetArrowFromDirectSum(product, productSource, coequList);
coequalizer = coequ.GetCoequalizer(first, second);
objectArrows = new List <IAdvancedCategoryArrow>();
foreach (IAdvancedCategoryArrow arrow in productArrows)
{
IAdvancedCategoryArrow arr = coequalizer.Compose(category, arrow);
objectArrows.Add(arr);
}
return(coequalizer.Target as IAdvancedCategoryObject);
}
/// <summary>
/// Creates limit
/// </summary>
private void CreateColim()
{
if (!(category is IDirectSumCategory))
{
throw new CategoryException(CategoryException.DirectSumNotSupported);
}
if (!(category is IEqualizerCategory))
{
throw new CategoryException(CategoryException.CoequalizerNotSupported);
}
IDirectSumCategory sumCategory = category as IDirectSumCategory;
IList <IAdvancedCategoryArrow> firstArrows = new List <IAdvancedCategoryArrow>();
IAdvancedCategoryObject firstSum = sumCategory.GetDirectSum(objects, firstArrows);
IList <IAdvancedCategoryObject> beginObjects = new List <IAdvancedCategoryObject>();
foreach (CategoryObjectPair o in arrows.Keys)
{
IAdvancedCategoryArrow a = arrows[o];
beginObjects.Add(a.Source as IAdvancedCategoryObject);
}
IList <IAdvancedCategoryArrow> secondArrows = new List <IAdvancedCategoryArrow>();
IAdvancedCategoryObject secondSum = sumCategory.GetDirectSum(beginObjects, secondArrows);
colimIdArrows = new List <IAdvancedCategoryArrow>();
foreach (IAdvancedCategoryArrow sar in secondArrows)
{
IAdvancedCategoryObject s = sar.Source as IAdvancedCategoryObject;
foreach (IAdvancedCategoryArrow proj in firstArrows)
{
if (proj.Source == s)
{
colimIdArrows.Add(proj);
break;
}
}
}
colimIdArrow = sumCategory.GetArrowFromDirectSum(firstSum, secondSum, colimIdArrows);
colimFuncArrows = new List <IAdvancedCategoryArrow>();
foreach (CategoryObjectPair o in arrows.Keys)
{
IAdvancedCategoryArrow sar = this[o];
foreach (IAdvancedCategoryArrow proj in firstArrows)
{
if (proj.Source == sar.Target)
{
IAdvancedCategoryArrow ar = proj.Compose(category, sar);
colimFuncArrows.Add(ar);
break;
}
}
}
colimFuncArrow = sumCategory.GetArrowFromDirectSum(firstSum, secondSum, colimFuncArrows);
ICoequalizerCategory coequalizerCategory = category as ICoequalizerCategory;
colimArrow = coequalizerCategory.GetCoequalizer(colimIdArrow, colimFuncArrow);
colim = colimArrow.Target as IAdvancedCategoryObject;
colimArrows = new Dictionary <IAdvancedCategoryObject, IAdvancedCategoryArrow>();
foreach (IAdvancedCategoryArrow proj in firstArrows)
{
IAdvancedCategoryObject s = proj.Source as IAdvancedCategoryObject;
IAdvancedCategoryArrow ar = colimArrow.Compose(category, proj);
colimArrows[s] = ar;
}
}
/// <summary>
/// Gets arrow from colim
/// </summary>
/// <param name="arrows">Arrows from objects</param>
/// <returns>Arrow from colim</returns>
public IAdvancedCategoryArrow GetArrowFromColim(IList <IAdvancedCategoryArrow> arrows)
{
Dictionary <ICategoryObject, ICategoryArrow> dictionary = new Dictionary <ICategoryObject, ICategoryArrow>();
IAdvancedCategoryObject target = null;
foreach (IAdvancedCategoryArrow arrow in arrows)
{
if (target == null)
{
target = arrow.Target as IAdvancedCategoryObject;
}
if (target != arrow.Target)
{
throw new CategoryException(CategoryException.DifferentTargets,
new IAdvancedCategoryObject[] { target, arrow.Target as IAdvancedCategoryObject });
}
if (!objects.Contains(arrow.Source as IAdvancedCategoryObject))
{
throw new CategoryException(ObjectOutOfDiagram, arrow.Source);
}
if (dictionary.ContainsKey(arrow.Source))
{
throw new CategoryException(ExtraArrow, arrow);
}
dictionary[arrow.Source] = arrow;
}
foreach (object o in objects)
{
if (!dictionary.ContainsKey(o as ICategoryObject))
{
throw new CategoryException(ArrowsShortage, o);
}
}
foreach (CategoryObjectPair pair in Keys)
{
IAdvancedCategoryArrow ar = this[pair];
IAdvancedCategoryArrow first = dictionary[pair.Target] as IAdvancedCategoryArrow;
IAdvancedCategoryArrow second = dictionary[pair.Source] as IAdvancedCategoryArrow;
IAdvancedCategoryArrow composition = first.Compose(category, ar);
if (!composition.Equals(second))
{
throw new CategoryException(CategoryException.NonCommutativePath, ar);
}
}
Dictionary <int, IAdvancedCategoryArrow> sortedTable = new Dictionary <int, IAdvancedCategoryArrow>();
foreach (IAdvancedCategoryArrow ar in arrows)
{
int i = objects.IndexOf(ar.Source as IAdvancedCategoryObject);
sortedTable[i] = ar;
}
IList <IAdvancedCategoryArrow> sortedArrows = new List <IAdvancedCategoryArrow>();
for (int i = 0; i < sortedTable.Count; i++)
{
sortedArrows.Add(sortedTable[i]);
}
IDirectSumCategory sumCategory = category as IDirectSumCategory;
IAdvancedCategoryArrow arrowFromSum =
sumCategory.GetArrowFromDirectSum(target, colimIdArrow.Target as IAdvancedCategoryObject, sortedArrows);
ICoequalizerCategory coequalizerCategory = category as ICoequalizerCategory;
IAdvancedCategoryArrow res = coequalizerCategory.GetArrowFromCoequalizer(colimArrow,
arrowFromSum, colimIdArrow, colimFuncArrow);
return(res);
}