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Bruger:Peh-herlev/sandkasse-Talrepresentation (Computer): Forskelle mellem versioner

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Linje 320:
Også kendt som '''floating point'''.
 
===Internal representation===
 
Flydende komma tal er typisk pakket i computer ord med følgende fælter : fortegn, eksponent og mantisse. Standarden [[IEEE 754]] er en standard for flydende decimal tal:
Floating-point numbers are typically packed into a computer datum as the sign bit, the exponent field, and the significand (mantissa), from left to right. For the IEEE 754 binary formats (basic and extended) which have extant hardware implementations, they are apportioned as follows:
 
{| class="wikitable" style="text-align: right;"
|-
!IEEE 754 Type
!Fortegn
!Eksponent
Line 336 ⟶ 335:
!Antal decimal cifre
|-
|[[IEEE 754 Half precision|Half]] ([[IEEE 754-2008]])
|1
|5
Line 346 ⟶ 345:
|~3.3
|-
|[[IEEE 754 Single precision|Single]]
|1
|8
Line 356 ⟶ 355:
|~7.2
|-
|[[IEEE 754 Double precision|Double]]
|1
|11
Line 366 ⟶ 365:
|~15.9
|-
|[[IEEE 754 Extended precision|Double extended (80-bit)]]
|1
|15
Line 376 ⟶ 375:
|~19.2
|-
|[[IEEE 754 Quad precision|Quad]]
|1
|15
Line 395 ⟶ 394:
! align="left" | Funktion:
! align="center" bgcolor="lightgray" | Fortegn
! •▼
!▼
! colspan="8" align="center" bgcolor="lightgray" | Eksponen
! •▼
!▼
! colspan="23" align="center" bgcolor="lightgray" | Mantisse
|-
! align="left" | Bit nummer
! align="center" bgcolor="lightgray" | 31
▲!
▲! •
! align="center" bgcolor="lightgray" | 30
! align="center" bgcolor="lightgray" | 29
Line 411 ⟶ 410:
! align="center" bgcolor="lightgray" | 24
! align="center" bgcolor="lightgray" | 23
▲!
▲! •
! align="center" bgcolor="lightgray" | 22
! align="center" bgcolor="lightgray" | 21
Line 481 ⟶ 480:
! align="left" | Funktion:
! align="center" bgcolor="lightgray" | Fortegn
! •▼
!▼
! colspan="8" align="center" bgcolor="lightgray" | Eksponen
! •▼
!▼
! colspan="23" align="center" bgcolor="lightgray" | Mantisse
|-
! align="left" | Bit nummer
! align="center" bgcolor="lightgray" | 31
▲!
▲! •
! align="center" bgcolor="lightgray" | 30
! align="center" bgcolor="lightgray" | 29
Line 497 ⟶ 496:
! align="center" bgcolor="lightgray" | 24
! align="center" bgcolor="lightgray" | 23
▲!
▲! •
! align="center" bgcolor="lightgray" | 22
! align="center" bgcolor="lightgray" | 21
Line 567 ⟶ 566:
! align="left" | Funktion:
! align="center" bgcolor="lightgray" | Fortegn
! •▼
!▼
! colspan="8" align="center" bgcolor="lightgray" | Eksponen
! •▼
!▼
! colspan="23" align="center" bgcolor="lightgray" | Mantisse
|-
! align="left" | Bit nummer
! align="center" bgcolor="lightgray" | 31
▲!
▲! •
! align="center" bgcolor="lightgray" | 30
! align="center" bgcolor="lightgray" | 29
Line 583 ⟶ 582:
! align="center" bgcolor="lightgray" | 24
! align="center" bgcolor="lightgray" | 23
▲!
▲! •
! align="center" bgcolor="lightgray" | 22
! align="center" bgcolor="lightgray" | 21
Line 653 ⟶ 652:
! align="left" | Funktion:
! align="center" bgcolor="lightgray" | Fortegn
! •▼
!▼
! colspan="8" align="center" bgcolor="lightgray" | Eksponen
! •▼
!▼
! colspan="23" align="center" bgcolor="lightgray" | Mantisse
|-
! align="left" | Bit nummer
! align="center" bgcolor="lightgray" | 31
▲!
▲! •
! align="center" bgcolor="lightgray" | 30
! align="center" bgcolor="lightgray" | 29
Line 669 ⟶ 668:
! align="center" bgcolor="lightgray" | 24
! align="center" bgcolor="lightgray" | 23
▲!
▲! •
! align="center" bgcolor="lightgray" | 22
! align="center" bgcolor="lightgray" | 21
Line 739 ⟶ 738:
! align="left" | Funktion:
! align="center" bgcolor="lightgray" | Fortegn
! •
!
! colspan="8" align="center" bgcolor="lightgray" | Eksponen
! •
!
! colspan="23" align="center" bgcolor="lightgray" | Mantisse
|-
! align="left" | Bit nummer
! align="center" bgcolor="lightgray" | 31
!•
! align="center" bgcolor="lightgray" | 30
! align="center" bgcolor="lightgray" | 29
Line 755 ⟶ 754:
! align="center" bgcolor="lightgray" | 24
! align="center" bgcolor="lightgray" | 23
!•
! align="center" bgcolor="lightgray" | 22
! align="center" bgcolor="lightgray" | 21
Hentet fra "https://da.wikipedia.org/wiki/Bruger:Peh-herlev/sandkasse-Talrepresentation_(Computer)"