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US5278987A Expired / Lapsed US ⏱️ 0.0 years remaining

Virtual pocket sorting

Assignee: PIERS MAPLE SPECIAL SITUATIONS LLC
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Filing: 1991-03-05
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Granted: 1994-01-11
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Expires: 2011-03-05
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Abstract

Abstract The present invention sorts very large volumes of data records by forming successive lists of sorted record start address by character rank from a LSD (least significant digit) of a sort field to a MSD (most significant digit) of such field with each list being formed in the order of the preceeding list. The present invention forms the lists by placing record start addresses in a collated list of virtual pockets wherein successive occurrences of like characters are linked to the next pocket memory position of such character so as to form the list in a memory requiring only the same number of addresses as there are records being sorted. The invention thus very materially reduces the size of pocket memory required for this type of data sorting.

Inventors

  • 👤 Franklin Chiang
  • 👤 Lawrence J. Thoman

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 13:17
CPC Classifications
G; G06; G06F; G06F7/00; G06F7/22; G06F7/24; Y; Y10; Y10S; Y10S707/00; Y10S707/99931; Y10S707/99937

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 186 words
An apparatus for sorting records of one or more characters stored in a data memory, comprising: a pair of source and destination memories having a numbered sequence of pockets for storing in each pocket an address and a pointer to a next pocket, a character memory having a corresponding location for each character in a collating order of characters, each location for storing an address, means for successively reading out an address from the source memory by following the pointers and selecting a character of a record stored at the address in the data memory, means for translating the character into a location in the character memory and storing the address in said location, means for reading out the address from the character memory only after an initial occurrence of the character and writing into a pocket in the destination memory, destination pocket number of a current occurrence of the character with an address of an immediately preceding occurrence of said character, means for reading the character memory in a descending order while linking addresses of initial occurrences and addresses already present in the destination memory.
Claim 2
Independent Claim 186 words
An apparatus for sorting records of one or more characters stored in a data memory, comprising: a pair of source and destination memories having a numbered sequence of pockets for storing in each pocket an address and a pointer to a next pocket, a character memory having a corresponding location for each character in a collating order of characters, each location for storing an address, means for successively reading out an address from the source memory by following the pointers and selecting a character of a record stored at the address in the data memory, means for translating the character into a location in the character memory and storing the address in said location, means for reading out the address from the character memory only after an initial occurrence of the character and writing into a pocket in the destination memory, destination pocket number of a current occurrence of the character with an address of an immediately preceding occurrence of said character, means for reading the character memory in a descending order while linking addresses of initial occurrences and addresses already present in the destination memory.
Claim 3
Dependent Claim 43 words
An apparatus for sorting records of one or more characters stored in a data memory, as in claim 1, further comprising: means for connecting the pair of memories to alternately serve as source and destination memories, and means for resetting the character memory.

References Cited (Backward Citations)

US3602899A Cited
US4295206A Cited
US4425626A Cited
US4559612A Cited
US4799149A Cited
US4680700A Cited
US4611280A Cited
US4809158A Cited
US4914577A Cited
US4905188A Cited
US5121493A Cited
US5117495A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1997-01-10 1997-07-12 1998-01-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2001-01-10 2001-07-12 2002-01-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2005-01-10 2005-07-12 2006-01-11 $7700.00 Window Closed / Lapsed

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