JPS5668834A - Logarithm converting device - Google Patents

Logarithm converting device

Info

Publication number
JPS5668834A
JPS5668834A JP14572879A JP14572879A JPS5668834A JP S5668834 A JPS5668834 A JP S5668834A JP 14572879 A JP14572879 A JP 14572879A JP 14572879 A JP14572879 A JP 14572879A JP S5668834 A JPS5668834 A JP S5668834A
Authority
JP
Japan
Prior art keywords
circuit
result
logarithm
conversion
information
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP14572879A
Other languages
Japanese (ja)
Other versions
JPS6013490B2 (en
Inventor
Takeshi Abe
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Toshiba Corp
Original Assignee
Toshiba Corp
Tokyo Shibaura Electric Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Toshiba Corp, Tokyo Shibaura Electric Co Ltd filed Critical Toshiba Corp
Priority to JP14572879A priority Critical patent/JPS6013490B2/en
Publication of JPS5668834A publication Critical patent/JPS5668834A/en
Publication of JPS6013490B2 publication Critical patent/JPS6013490B2/en
Expired legal-status Critical Current

Links

Landscapes

  • Complex Calculations (AREA)

Abstract

PURPOSE: To realize a high-precision logarithm conversion in a simple constitution, by making use of a rational approximate calculation using the mathematical logarithm law and thus decreasing greatly the number of necessary numerical tables.
CONSTITUTION: The control circuit 7 repeats the same action to give a digit shift and subtraction command unless carry information is delivered from the data holding circuit 1 as a result of digit shift, and then gives the data or the like of the circuit 1 to the memory circuit 5 in the form of the selection designating information as the result in case the carry information is delivered. Then the circuit 7 selects the specified memory data corresponding to the information through the circuit 5, and furthermore gives an addition command to the adder circuit 6 to deliver the result of addition in the form of the logarithm conversion value of Y=KlogaX to the input X. Thus a rational approximate calculation using the mathematical logarithm law is applied to reduce greatly the number of numerical tables necessary for conversion. As a result, a high-precision logarithm conversion is possible in a simple constitution.
COPYRIGHT: (C)1981,JPO&Japio
JP14572879A 1979-11-10 1979-11-10 Logarithmic conversion device Expired JPS6013490B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP14572879A JPS6013490B2 (en) 1979-11-10 1979-11-10 Logarithmic conversion device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP14572879A JPS6013490B2 (en) 1979-11-10 1979-11-10 Logarithmic conversion device

Publications (2)

Publication Number Publication Date
JPS5668834A true JPS5668834A (en) 1981-06-09
JPS6013490B2 JPS6013490B2 (en) 1985-04-08

Family

ID=15391754

Family Applications (1)

Application Number Title Priority Date Filing Date
JP14572879A Expired JPS6013490B2 (en) 1979-11-10 1979-11-10 Logarithmic conversion device

Country Status (1)

Country Link
JP (1) JPS6013490B2 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6319037A (en) * 1986-07-11 1988-01-26 Fujitsu Ltd Logarithm conversion system for data
US5197024A (en) * 1989-06-14 1993-03-23 Pickett Lester C Method and apparatus for exponential/logarithmic computation
EP0755121A2 (en) * 1995-07-21 1997-01-22 Nec Corporation Exponential and logarithmic conversion circuit

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6319037A (en) * 1986-07-11 1988-01-26 Fujitsu Ltd Logarithm conversion system for data
US5197024A (en) * 1989-06-14 1993-03-23 Pickett Lester C Method and apparatus for exponential/logarithmic computation
EP0755121A2 (en) * 1995-07-21 1997-01-22 Nec Corporation Exponential and logarithmic conversion circuit
EP0755121A3 (en) * 1995-07-21 2000-07-05 Nec Corporation Exponential and logarithmic conversion circuit

Also Published As

Publication number Publication date
JPS6013490B2 (en) 1985-04-08

Similar Documents

Publication Publication Date Title
JPS5345949A (en) Arithmetic unit for n-point discrete fourier conversion
JPS52132443A (en) Electronic range capable of operating cooking programs
JPS5668834A (en) Logarithm converting device
JPS5532161A (en) Integration processing unit
JPS55127638A (en) Digital arithmetic unit
JPS52147287A (en) Process control equipment
JPS5365021A (en) Display unit
JPS5245850A (en) Data input equipment
JPS53123793A (en) Input reaction degree restricting apparatus
JPS5222454A (en) Computation control method
JPS5552137A (en) Character output system
JPS5478940A (en) Code conversion system
JPS5510688A (en) Control circuit
JPS5347243A (en) Logarithmic arithmetic unit
JPS5294746A (en) Electronic apparatus
JPS55105766A (en) Electronic calculator
JPS5533204A (en) Digital control system
JPS5411637A (en) Tablet unit
JPS5377148A (en) Input and output control circuit
JPS54108545A (en) Semiconductor device of bit slice type
JPS52147292A (en) Adapted sequence controller
JPS54158154A (en) Method and apparatus for analog-digiral conversion
JPS53121533A (en) Multiplier circuit system
JPS5794849A (en) Microprogram controller
JPS5453835A (en) Character pattern generation system