Zero suppression

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

Template:Multiple issues

File:Casio AX-120V.JPG
An electronic calculator with zero suppression, showing 123 instead of 000000000123

Zero suppression is the removal of redundant zeroes from a number. This can be done for storage, page or display space constraints or formatting reasons, such as making a letter more legible.[1][2][3]

Examples

  • 00049823 → 49823
  • 7.678600000 → 7.6786
  • 0032.3231000 → 32.3231
  • 2.45000×1010 → 2.45×1010
  • 0.0045×1010 → 4.5×107

One must be careful; in physics and related disciplines, trailing zeros are used to indicate the precision of the number, as an error of ±1 in the last place is assumed. Examples:

  • 4.5981 is 4.5981 ± 0.0001
  • 4.59810 is 4.5981 ± 0.00001
  • 4.598100 is 4.5981 ± 0.000001Script error: No such module "Unsubst".

Data compression

It is also a way to store a large array of numbers, where many of the entries are zero. By omitting the zeroes, and instead storing the indices along with the values of the non-zero items, less space may be used in total. It only makes sense if the extra space used for storing the indices (on average) is smaller than the space saved by not storing the zeroes. This is sometimes used in a sparse array.Script error: No such module "Unsubst".

Example:

  • Original array: 0, 1, 0, 0, 2, 5, 0, 0, 0, 4, 0, 0, 0, 0, 0
  • Pairs of index and data: {2,1}, {5,2}, {6,5}, {10,4}

See also

References

Template:Reflist

  1. Cite error: Invalid <ref> tag; no text was provided for refs named bldr
  2. Cite error: Invalid <ref> tag; no text was provided for refs named ICH
  3. Cite error: Invalid <ref> tag; no text was provided for refs named Auto