Intersection is a term that relates to descriptive geometry and functions. Intersections are points which are included in multiple objects. They are intersections of the object they belong to.
Questions tagged [intersection]
2483 questions
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How to check intersection between 2 rotated rectangles?
Can someone explain how to check if one rotated rectangle intersect other rectangle?
Buron
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Efficiently find points inside a circle sector
I have a set of 2d points distributed randomly. I need to perform a time intensive operation on a small subset of these points but I need to first figure out what points I need to perform this time intensive operation on. To determine what points I…
ApockofFork
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How to intersect two polygons?
This seems non-trivial (it gets asked quite a lot on various forums), but I absolutely need this as a building block for a more complex algorithm.
Input: 2 polygons (A and B) in 2D, given as a list of edges [(x0, y0, x1, y2), ...] each. The points…
Daren Thomas
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Determining if two rays intersect
I have two rays on a 2D plane that extend to infinity, but both have a starting point. They are both described by a starting point and a vector in the direction of the ray extending to infinity. I want to find out if the two rays intersect, but I…
Faken
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Vector intersection in C++
I have this function
vector instersection(const vector &v1, const vector &v2);
I have two vectors of strings and I want to find the strings that are present in both, which then fills a third vector with the common elemnts.…
Tyler
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Intersection of two pandas dataframes based on column entries
Suppose I have two DataFrames like so:
>>dfA
S T prob
0 ! ! ! ! ! ! 8.1623999e-05
1 ! ! ! ! ! ! " 0.00354090007
2 ! ! ! ! ! ! . 0.00210241997
3 ! ! ! ! ! ! ? 6.55684998e-05
4 ! ! ! ! ! ! …
Bib
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Efficient extraction of all sub-polygons generated by self-intersecting features in a MultiPolygon
Starting from a shapefile containing a fairly large number (about 20000) of potentially partially-overlapping polygons, I'd need to extract all the sub-polygons originated by intersecting their different "boundaries".
In practice, starting from…
lbusett
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Area of Intersection of Two Rotated Rectangles
I have two 2D rectangles, defined as an origin (x,y) a size (height, width) and an angle of rotation (0-360°). I can guarantee that both rectangles are the same size.
I need to calculate the approximate area of intersection of these two…
Nate Thorn
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Algorithm for determining whether a point is inside a 3D mesh
What is a fast algorithm for determining whether or not a point is inside a 3D mesh? For simplicity you can assume the mesh is all triangles and has no holes.
What I know so far is that one popular way of determining whether or not a ray has…
Jeff Jenkins
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2d game : fire at a moving target by predicting intersection of projectile and unit
Okay, this all takes place in a nice and simple 2D world... :)
Suppose I have a static object A at position Apos, and a linearly moving object B at Bpos with bVelocity, and an ammo round with velocity Avelocity...
How would I find out the angle that…
Led
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Check if two line segments are colliding (only check if they are intersecting, not where)
I need a fast algorithm for checking if two non-infinite lines are crossing. Have to be fast because it'll run on a cell phone a lot.
The algorithm do only have to return yes or no, it does not have to find out exactly where the lines cross!
I have…
Mike
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Area of intersection between circle and rectangle
I'm looking for a fast way to determine the area of intersection between a rectangle and a circle (I need to do millions of these calculations).
A specific property is that in all cases the circle and rectangle always have 2 points of intersection.
user67424
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How to intersect multiple sets?
I have this list:
private List> scanList;
So my list contains multiple scans as you can see.
After each scan I add new set into the list.
After all scans are finished I would like to take only the addresses that occur in every set and…
vale4674
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Compute the area of intersection between a circle and a triangle?
How does one compute the area of intersection between a triangle (specified as three (X,Y) pairs) and a circle (X,Y,R)? I've done some searching to no avail. This is for work, not school. :)
It would look something like this in C#:
struct {…
Mark Maxham
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Ray-box Intersection Theory
I wish to determine the intersection point between a ray and a box. The box is defined by its min 3D coordinate and max 3D coordinate and the ray is defined by its origin and the direction to which it points.
Currently, I am forming a plane for each…
Myx
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