Tool to calculate all paths on a lattice graphe (square grid graph). A path is a series of directions (north, south, east, west) to connect two points on a grid.
Lattice Path - dCode
Tag(s) : Graph Theory
dCode is free and its tools are a valuable help in games, maths, geocaching, puzzles and problems to solve every day!
A suggestion ? a feedback ? a bug ? an idea ? Write to dCode!
Lattice Path
Path Count Calculator (North-East - NE)
The information on this page is for a square grid and is not valid on triangular grids (or other non square lattice graphs).
Answers to Questions (FAQ)
How to count paths on a lattice graph?
The calculation of the number of paths (of length $ a + b $) on a grid of size (a x b) (limited to a north-south direction and a west-east direction) uses combinatorics tools such as the binomial coefficient $ \binom{a+b}{a} $
The north direction N consists of moving up one unit along the ordinate (0,1).
The east direction E consists of moving one unit to the right along the abscissa (1,0).
Example: To go from the point $ (0, 0) $ to the point $ (2, 2) $ (which corresponds to a 2x2 grid) using only north and east. (N,N,E,E), (N,E,N,E), (N,E,E,N), (E,N,E,N), (E,N,N,E), (E,E,N,N) so 6 paths and is computed $ \binom{4}{2} = 6 $
What is a lattice graph?
A grid graph is the name given to a bounded grid (with borders).
How to enumerate pathways in a lattice graph?
To generate the list of all paths, use the permutation generator.
Example: N,N,N,E has 4 distinct permutations: (N,N,N,E) (N,N,E,N) (E,N,N,N) (N,E,N,N)
Source code
dCode retains ownership of the "Lattice Path" source code. Except explicit open source licence (indicated Creative Commons / free), the "Lattice Path" algorithm, the applet or snippet (converter, solver, encryption / decryption, encoding / decoding, ciphering / deciphering, translator), or the "Lattice Path" functions (calculate, convert, solve, decrypt / encrypt, decipher / cipher, decode / encode, translate) written in any informatic language (Python, Java, PHP, C#, Javascript, Matlab, etc.) and all data download, script, or API access for "Lattice Path" are not public, same for offline use on PC, tablet, iPhone or Android !
The copy-paste of the page "Lattice Path" or any of its results, is allowed as long as you cite the online source
Reminder : dCode is free to use.
