apcj

  // Available variables:
  // - Machine
  // - interpret
  // - assign
  // - send
  // - sendParent
  // - spawn
  // - raise
  // - actions

apcj

MERGE (person:Person{name:"Alistair"})
MERGE (role:Role{name:"Software Engineer"})
MERGE (company:Company{name:"Neo Technology"})
CREATE (empl:Employment{from: 2011})

MERGE (person)-[:CURRENT]->(empl)
MERGE (empl)-[:WORKS_AT]->(company)
MERGE (empl)-[:ROLE]->(role)

// Determine whether first story already exists

apcj

This simple force-directed graph shows character co-occurence in Les Misérables. A physical simulation of charged particles and springs places related characters in closer proximity, while unrelated characters are farther apart. Layout algorithm inspired by Tim Dwyer and Thomas Jakobsen. Data based on character coappearence in Victor Hugo's Les Misérables, compiled by Donald Knuth.

Compare this display to a force layout with curved links, a force layout with fisheye distortion and a matrix diagram.

apcj

Run simple cypher queries via the Neo4j Transactional Cypher HTTP endpoint to estimate the HTTP overhead.

Request serialisation and response deserialisation using Jackson. HTTP using Apache HTTP Client.

Example output:

result = 1

apcj

#!/usr/bin/python

import os
import xml.etree.ElementTree as xml

ns = '{http://maven.apache.org/POM/4.0.0}'

print 'MATCH (n) OPTIONAL MATCH (n) -[r]-> () DELETE n, r;'

def mergeProject(domElement, variableName):

apcj

In 2010, Mexico gained revenge over France for beating them in 1930 after a wait of 80 years
In 1986, Argentina gained revenge over Uruguay for beating them in 1930 after a wait of 56 years
In 2010, Mexico gained revenge over France for beating them in 1954 after a wait of 56 years
In 1986, Brazil gained revenge over Spain for beating them in 1934 after a wait of 52 years
In 1982, France gained revenge over Austria for beating them in 1934 after a wait of 48 years
In 1986, France gained revenge over Italy for beating them in 1938 after a wait of 48 years
In 2006, France gained revenge over Brazil for beating them in 1958 after a wait of 48 years
In 2010, Switzerland gained revenge over Spain for beating them in 1966 after a wait of 44 years
In 1978, Brazil gained revenge over Italy for beating them in 1938 after a wait of 40 years
In 1998, France gained revenge over Brazil for beating them in 1958 after a wait of 40 years

apcj

MATCH (c1:Country)
MATCH (c2:Country)
WHERE c1 <> c2
WITH c1, c2, 2 * 6371 * asin(sqrt(haversin(radians(c1.lat - c2.lat))+ cos(radians(c1.lat))*
  cos(radians(c2.lat))* haversin(radians(c1.lon - c2.lon)))) AS dist
WHERE dist > 0
RETURN c1.name, c2.name, dist
ORDER BY dist
LIMIT 1000

apcj

MATCH (s:Squad) -[:BEAT]-> () -[:BEAT]-> (s)
RETURN s

apcj

data.tsv

apcj

Smooth graph exploration

D3 force layout keeps track of node positions by setting x and y properties on the underlying data. By default it chooses starting positions at random, which is convenient, but leads to high-velocity, distracting movements when force calculations begin.

For many graph structures, it's easy to do better than random for starting positions. We can set specific start positions on the data before handing over control to force layout.

In this example, clicking on a node expands its 10 immediate neighbours. For a short period