Hello everyone,
I am a new memeber, and I need help in c++ code.
Actually I had a code that need kd tree data structure in order to find the nearest neighbour, so I found a kd tree that had been written in c++ as class and there is a function which specialized to find the parent of any given point and it starts with assigning a pointer by " this " and actaully I didn't understand it and in the mean time I didn't find good resources that explaine what does " this " means in general..is it special for classes or just stansered viriable and what does it mean
The function looks like that :

KDNODE*	KDNODE::FindParent(Xtype* x0)
    KDNODE* parent ;
    KDNODE* next = this ;
    int split ;
        split = next->axis  ;
        parent = next ;
        if(x0[split] > next->x[split])
            next = next->Right ;
            next = next->Left ;
    return parent ;

The entire stuff that related with this code is in the following link:


I thank you all in advance for any kind of help or advices

10 Years
Discussion Span
Last Post by sheree

this is apointer to the current object of the class which function is member of.

i will be pleasure if i help you


this is a hidden parameter that is passed to every non-static method of a c++ class. It is used to point to a specific instance of a class and all its data object. In your specdific problem FindParent() is called from a specif node in the list, and the this parameter that is passed to that method by c++ is a pointer to that node.


thanks farag, thanks Ancient Dragon,
but Ancient Dragon, I still wundering about that pointer.
If I understood well, then this will point to the node that I wan to find its nearest neighbour,......but then how can I find its parent while it is not a node belongs to the kd tree , as it mentioned in FindParent()
I'll appricate any more detail.

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