dst (version 1.8.0)

decode: Find the value in base 10 of a number coded in another base

Description

The aplDecode function of the project APL in R (https://rpubs.com/deleeuw/158476) has been adapted to follow the standard implementation of the APL decode function.

Usage

decode(base, ind)

Value

A scalar representing the conversion of the coded number ind to its decimal representation.

Arguments

base

A scalar or a numeric vector which describes the number system in which the data is coded.

ind

The value to decode represented by a numeric vector in the base system.

Author

Claude Boivin

Details

If the base value is a number system, e.g. base 2, we need only to enter it as a scalar, which is then processed to match the length of the expression to decode. If length(ind) is less than length(base), zeroes are added to the left of the vector ind to match the length of the two vectors. And vice-versa.

References

• Jan de Leeuw and Masanao Yajima (March 07, 2016) APL in R (Version 009), Source code. https://rpubs.com/deleeuw/158476

• L. Gilman and A. J. Rose.(1974): APL an Interactive Approach, Second Edition, John Wiley, New York.

• APL 68000 Level II language manual. MicroAPL Ltd. 1990.

Examples

decode(c(2,2,2,2), c(1,0,1,1)) #   Find the base 10 value of the base 2 number 1011.
decode(2, c(1,0,1,1))  # left argument is extended to vector c(2,2,2,2)
decode(c(365,24,60), c(2,1,57)) # transform 2 days 1 h 57 min in minutes
decode(c(365,24,60), c(1,57))   # right vector extended
decode(c(24,60), c(2,1,57))     # left vector extended
decode(1.5, c(1,2,3)) # polynomial 1*x^2 +2*x +3 evaluated at x=1.5