How to sort an ObjectList in Digital Micrograph - dm-script

Question

Is it any possibilities to sort the ObjectList object?
For example:
class MissPlane: object
{
number d_local
object init(object self, number d)
{
d_local=d
return self
}
number getD(object self)
{
return d_local
}
void print(object self)
{
result("d="+d_local+"\n")
}
}
number h,k,l,hmax
hmax=2
result("start----------------"+datestamp()+"----------------------\n")
Object PlaneList
PlaneList=Alloc(ObjectList)
for(l=-hmax;l<=hmax;l++){
for(k=-hmax;k<=hmax;k++){
for(h=-hmax;h<=hmax;h++){
Object MPObject=Alloc(MissPlane)
MPObject.init(random())
PlaneList.AddObjectToList(MPObject)
MPObject.print()
}
}
}
And finally I need to sort it by d.
PS. ObjectList is not fully documented in the DM manual.

Answer 1

You can use the DM command sort to achieve sorting of either TagLists or ObjectList. In both cases you have to create a "sorting" class which defines a method comparing two elements and returning if the second element is bigger than the first.
The following example is for TagLists, sorting a numeric tagList to have increasing numbers.
Class Sorter
{
// The signature of the following method must not be changed.
Number Bigger( Object self, TagGroup TG1, Number index1, TagGroup TG2, Number index2 )
{
Number N1, N2
TG1.TagGroupGetIndexedTagAsNumber( index1, N1 )
TG2.TagGroupGetIndexedTagAsNumber( index2, N2 )
return (N1<N2)?1:0
}
}
TagGroup CreateRandomList( Number n )
{
TagGroup list = NewTagList()
For ( Number i = 0 ; i < n ; i++ )
list.TagGroupInsertTagAsNumber( i, Random() )
return list
}
void Main()
{
TagGroup unsorted = CreateRandomList( 10 )
unsorted.TagGroupOpenBrowserWindow( "unsorted", 0 )
Object sortObject = Alloc( Sorter )
Sort( 0, unsorted, sortObject, "Bigger" ) // The first parameter specifies ‘stable’ search
unsorted.TagGroupOpenBrowserWindow( "sorted", 0 )
}
Main()
The next example is for ObejctLists, sorting an objectList. In this case, objects of the list are simply "wrapped numbers" and the soring again achieves an increasing numbers.
class MyObject
{
Number value
Object Init( Object self, Number in ) { value = in; return self; }
Number Get( Object self ) { return value; }
}
Class Sorter
{
// The signature of the following method must not be changed.
Number HigherValue( Object self, Object obj1, Object obj2 )
{
return ( obj1.Get() < obj2.Get() ) ? 1 : 0
}
}
Object CreateRandomList( Number n )
{
Object obList = Alloc(ObjectList)
For ( Number i = 0 ; i < n ; i ++ )
{
Object newOBJ = Alloc(MyObject).Init( Random() )
obList.AddObjectToList( newOBJ )
}
return obList
}
void PrintObjects( Object obList )
{
ForEach( Object ob; obList )
Result( "value:" + ob.Get() + "\n" )
}
void Main()
{
Object unsorted = CreateRandomList( 7 )
Result( "\nBefore sort:\n" )
unsorted.PrintObjects()
Result( "\nAfter sort:\n" )
Sort( 0, unsorted, Alloc(Sorter), "HigherValue" )
unsorted.PrintObjects()
}
Main()
Both code examples have been found from this website.

Answer 2

The following example create a simple "bubble-sort" method to sort your object list:
class MissPlane: object
{
number d_local
object init(object self, number d)
{
d_local=d
return self
}
number getD(object self)
{
return d_local
}
void print(object self)
{
result("d="+d_local+"\n")
}
}
object sortList( object in )
{
object copy = in.ScriptObjectClone() // Making a copy avoids messing with your original list...
object sorted=Alloc(objectlist)
while( copy.SizeOfList() )
{
object t = copy.ObjectAt(0)
for (number c=1; c<copy.SizeOfList(); c++ )
{
if ( t.GetD() > copy.ObjectAt(c).GetD() )
t = copy.ObjectAt(c); // found a "smaller" object
}
sorted.AddObjectToList(t) // add the smallest item found
copy.RemoveObjectFromList(t)
}
return sorted
}
number h,hmax
hmax=20
result("start----------------"+datestamp()+"----------------------\n")
Object PlaneList
PlaneList=Alloc(ObjectList)
for(h=-0;h<hmax;h++){
Object MPObject=Alloc(MissPlane)
MPObject.init(random())
PlaneList.AddObjectToList(MPObject)
}
result("start---------------- ORIGINAL ----------------------\n")
ForEach( object o; PlaneList )
o.print()
Object sorted = sortList(PlaneList)
result("start---------------- SORTED ----------------------\n")
ForEach( object o; sorted)
o.print()