NAME
    logn -  base n logarithm

SYNOPSIS
    logn(x, n [,eps])

TYPES
    x		nonzero real or complex
    n		nonzero real or complex
    eps		nonzero real, defaults to epsilon()

    return	real or complex

DESCRIPTION
    Approximate the base n logarithm function of x by a multiple of
    epsilon, the error having absolute value less than 0.75 * eps.

    The base, n, must not be 0 nor 1.

    If y is a positive integer, log(x, n^-y) will usually be correct
    to the y-th decimal place.

EXAMPLE
    ; print logn(15.625, 2.5), logn(15.625, 2.5, 1e-25)
    ~3.00000000000000000001 3

    ; print logn(127, 1/13), log(23209, sqrt(3)), logn(2^17-19, 17)
    ~-1.88860925162778125111 6 ~4.15900804831225415076

    ; print logn(-1, 1i), logn(2+3i, 3i+2), logn(2+3i, 3i)
    2 1 ~0.80360095345990217753-~0.25441159318835790311i

    ; print logn(22+3i, 3i, 1e-50)
    ~0.98489914201047045408-~1.28484657882287682702i

LIMITS
    x != 0
    n != 0 && n != 1
    eps > 0

LINK LIBRARY
    NUMBER *qlogn(NUMBER *x, NUMBER *n, NUMBER *eps)
    COMPLEX *c_logn(COMPLEX *x, COMPLEX *n, NUMBER *eps)

SEE ALSO
    ilog, ilogn, ilog10, ilog2, ln, log, log2

## Copyright (C) 2023  Landon Curt Noll
##
## Calc is open software; you can redistribute it and/or modify it under
## the terms of the version 2.1 of the GNU Lesser General Public License
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## Calc is distributed in the hope that it will be useful, but WITHOUT
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## or FITNESS FOR A PARTICULAR PURPOSE.	 See the GNU Lesser General
## Public License for more details.
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## Under source code control:	2023/08/19 09:14:04
## File existed as early as:	2023
##
## chongo <was here> /\oo/\	http://www.isthe.com/chongo/
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