Editing Intel 8087 (section)

===Infinity===

The 8087 handles [[infinity]] values by either [[Affine space|affine closure]] or [[Projective space|projective closure]] (selected by the status register). With affine closure, positive and negative infinities are treated as different values. With projective closure, infinity is treated as an unsigned representation for very small or very large numbers.{{sfn|Sanchez|Canton|2007|p=110}} These two methods of handling infinity were incorporated into the draft version of the [[IEEE floating point|IEEE 754]] floating-point standard. However, projective closure ([[projectively extended real number system]]) was dropped from the later formal issue of IEEE 754-1985. The 80287 retained projective closure as an option, but the 80387 and subsequent floating-point processors (including the 80187) only supported affine closure.