The table of chords, created by the astronomer, geometer, and geographer Ptolemy in Egypt during the 2nd century AD, is a trigonometric table in Book I, chapter 11 of Ptolemy's Almagest, a treatise on mathematical astronomy. It is essentially equivalent to a table of values of the sine function. It was the earliest trigonometric table extensive enough for many practical purposes, including those of astronomy (an earlier table of chords by Hipparchus gave chords only for arcs that were multiples of 7½° = π/24 radians). Centuries passed before more extensive trigonometric tables were created. One such table is the Canon Sinuum created at the end of the 16th century.
Attributes  Values 

rdf:type  
rdfs:label 

rdfs:comment 

sameAs  
dct:subject  
Wikipage page ID 

Wikipage revision ID 

Link from a Wikipage to another Wikipage 

Link from a Wikipage to an external page  
foaf:depiction  
foaf:isPrimaryTopicOf  
thumbnail  
prov:wasDerivedFrom  
has abstract 

http://purl.org/voc/vrank#hasRank  
http://purl.org/li...ics/gold/hypernym  
is Link from a Wikipage to another Wikipage of 

is Wikipage redirect of  
is foaf:primaryTopic of 