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Questions tagged [topology]

Topology is the mathematical study of the properties that are preserved through deformations, twistings, and stretchings of objects. Tearing, however, is not allowed. A circle is topologically equivalent to an ellipse (into which it can be deformed by stretching) and a sphere is equivalent to an ellipsoid.

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What is the "task" in Storm parallelism

I'm trying to learn twitter storm by following the great article "Understanding the parallelism of a Storm topology" However I'm a bit confused by the concept of "task". Is a task an running instance of the component(spout or bolt) ? A executor…
John Wang
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Find the shortest fence that encloses an area on a 2D grid

I have a 50 x 50 2D grid. Grid cells can have one of three states: 1: "inside" 2: "empty" 3: "wall" My initial configuration is a grid with some cells (maybe 10% of them, mostly contiguous) marked as "inside". Randomly there are some "wall" cells…
John Shedletsky
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comparing open source java graph drawing frameworks(JUNG and Prefuse) for drawing network topology

which of the open source Java graph drawing frameworks to use for a network diagram with the following requirements? The graph will have less than 1000 nodes. 1) has parallel edges 2) directed and undirected edges within a single graph 3) nodes…
user572964
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Why use st_intersection rather than st_intersects?

st_intersection is very slow compared to st_intersects. So why not use the latter instead of the former? Here's an example with a small toy dataset, but the difference in execution time is huge for my actual set of just 62,020 points intersected…
syre
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Most general higher-order constraint describing a sequence of integers ordered with respect to a relation

In CLP(FD), we frequently need to state: "This is a list of integers and finite domain variables in (sometimes: strictly) ascending/descending order." Is there any CLP(FD) system that provides a general (parametrisable) built-in constraint for this…
mat
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graph - What are the differences between Embedded and Topological in Graph?

In Algorithm Design Manual, page 178 describes some properties of Graph, and one of them is embedded and Topological: Embedded vs. Topological A graph is embedded if the vertices and edges are assigned geometric positions. Thus, any drawing of a…
Jackson Tale
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Topological data analysis - where to begin

I've recently come across 'topological data analysis' (TDA) as a unique way of visualizing large datasets. Here is a Stanford paper with example output towards the end https://research.math.osu.edu/tgda/mapperPBG.pdf. I'd like to produce similar…
Ben
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Tessellating an arbitrary polygon by tiling triangles

I need to fill an arbitrary polygon using a near-uniform tiling of triangles. How would I do this? You may provide either references to existing algorithms or even simply ideas or hints of your own. The following is presumed: The polygon may be…
Rehno Lindeque
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Network Map Algorithm that Detects Unmanaged Layer 2 Switches?

I've inherited a network spread out over a warehouse/front office consisting of approximately 50 desktop PCs, various servers, network printers, and routers/switches. The "intelligent" routers live in the server room. As the company has grown, we've…
Matt Rogish
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Using JTS, how to find the nearest point on a polygon's boundary from an outside point?

Using JTS, how to find the nearest point on a polygon's boundary from an outside point?
user521044
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"Center of Mass" between a set of points on a Toroidally-Wrapped Map that minimizes average distance to all points

edit As someone has pointed out, what I'm looking for is actually the point minimizing total geodesic distance between all other points My map is topographically similar to the ones in Pac Man and Asteroids. Going past the top will warp you to the…
Justin L.
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How to set bandwidth on Mininet custom topology?

I want to set bandwidth on Mininet custom topology. The python code is: #!/usr/bin/python from mininet.topo import Topo from mininet.net import Mininet from mininet.node import CPULimitedHost from mininet.link import TCLink from mininet.util import…
NWOWN
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TopologicalError: The operation 'GEOSIntersection_r' could not be performed

Hi Guys, I am trying to map the district shapefile into assembly constituencies. I have shape files for Both.Basically I have to map all the variables given at district level in census data to assembly constituency level. So I am following a pycon…
jatin rajani
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Defining non-unary functions in Cubical mode

I'd like to define a function with two, higher inductive typed, arguments in Cubical mode. I am using the cubical package as my "prelude" library. I first define a quotient type for integers as a HIT: {-# OPTIONS --cubical #-} module _ where open…
Cactus
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MPI_Cart_Shift.Corner Neighborhood

I need to create a communicator with cube topology and then select face of the cube, using the MPI_Cart_Shift implemented messaging between processes that are on the brink. For example I am process with rank 0(R0) my neighborhoods are R2, R4,…
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