Patents by Inventor Michael Frederic Cowlishaw

Michael Frederic Cowlishaw has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8560591
    Abstract: Detection of whether a result of a floating point operation is safe. Characteristics of the result are examined to determine whether the result is safe or potentially unsafe, as defined by the user. An instruction is provided to facilitate detection of safe or potentially unsafe results.
    Type: Grant
    Filed: April 25, 2007
    Date of Patent: October 15, 2013
    Assignee: International Business Machines Corporation
    Inventors: Shawn D. Lundvall, Ronald M. Smith, Sr., Phil C. Yeh, Michael Frederic Cowlishaw
  • Patent number: 7953784
    Abstract: Detection of whether a result of a floating point operation is safe. Characteristics of the result are examined to determine whether the result is safe or potentially unsafe, as defined by the user. An instruction is provided to facilitate detection of safe or potentially unsafe results.
    Type: Grant
    Filed: April 25, 2007
    Date of Patent: May 31, 2011
    Assignee: International Business Machines Corporation
    Inventors: Shawn D. Lundvall, Ronald M. Smith, Sr., Phil C. Yeh, Michael Frederic Cowlishaw
  • Patent number: 7685214
    Abstract: A method for conversion between a decimal floating-point number and an order-preserving format has been disclosed. The method encodes numbers in the decimal floating-point format into a format which preserves value ordering. This encoding allows for fast and direct string comparison of two values. Such an encoding provides normalized representations for decimal floating-point numbers and supports type-insensitive comparisons. Type-insensitive comparisons are often used in database management systems, where the data type is not specified for values to compare. In addition, the original decimal floating-point format can be recovered from the order-preserving format.
    Type: Grant
    Filed: August 26, 2005
    Date of Patent: March 23, 2010
    Assignee: International Business Machines Corporation
    Inventors: Yao-Ching Stephen Chen, Michael Frederic Cowlishaw, Christopher J. Crone, Fung Lee, Ronald Morton Smith, Sr., Guogen Zhang, Qinghua Zou
  • Patent number: 6525679
    Abstract: A system and method are provided for encoding from decimal to binary and back again. The coding is based on representing 3 decimal digits as 10 binary bits and is a development of the Chen-Ho algorithm. This provides a storage efficiency of >99%, yet still allows decimal arithmetic to be readily performed. The decimal input is typically first converted to binary coded decimal (4 bits per decimal digit), before compression to 10 bits. Adopting the encoding of the present invention, if the leading (most significant) decimal digit is zero, then the first three bits of the binary output are zero; and if the first two decimal digits are zero, then the first six bits of the binary output are zero. Accordingly, the same coding can be flexibly used to code a decimal digit is binary bits and 1 decimal digit is 4 binary bits. This makes it particularly suitable for standard computer architectures which are based on a power of two (16-bit, 32-bit, 64-bit, etc), and therefore not directly divisible by 7 or by 10.
    Type: Grant
    Filed: May 20, 2002
    Date of Patent: February 25, 2003
    Assignee: International Business Machines Corporation
    Inventor: Michael Frederic Cowlishaw
  • Patent number: 6437715
    Abstract: A system and method are provided for encoding from decimal to binary and back again. The coding is based on representing 3 decimal digits as 10 binary bits and is a development of the Chen-Ho algorithm. This provides a storage efficiency of >99%, yet still allows decimal arithmetic to be readily performed. The decimal input is typically first converted to binary coded decimal (4 bits per decimal digit), before compression to 10 bits. Adopting the encoding of the present invention, if the leading (most significant) decimal digit is zero, then the first three bits of the binary output are zero; and if the first two decimal digits are zero, then the first six bits of the binary output are zero. Accordingly, the same coding can be flexibly used to code 2 decimal digits to 7 binary bits, and 1 decimal digit to 4 binary bits. This makes it particularly suitable for standard computer architectures which are based on a power of two (16-bit, 32-bit, 64-bit, etc), and therefore not directly divisible by 7 or by 10.
    Type: Grant
    Filed: August 17, 2001
    Date of Patent: August 20, 2002
    Assignee: International Business Machines Corporation
    Inventor: Michael Frederic Cowlishaw