log

Returns the natural log of x (x positive only).

In the case of an array input, the operation can have an optional arbitrary base.

The argument value is restricted for log, log10, and sqrt.

Syntax

log({a,k,i,Complex}) 
log({k[],i[],Complex[]}) 
kout[] log kin[], ibas

where the argument within the parentheses may be an expression. Value converters perform arithmetic translation from units of one kind to units of another. The result can then be a term in a further expression. In the case of an array input, ibas is the optional arbitrary base, which defaults to e (natural log base).

Examples

Here is an example of the log opcode. It uses the file log.csd.

<CsoundSynthesizer>
<CsOptions>
; Select audio/midi flags here according to platform
; Audio out   Audio in
-odac           -iadc    ;;;RT audio I/O
; For Non-realtime ouput leave only the line below:
; -o log.wav -W ;;; for file output any platform
</CsOptions>
<CsInstruments>

; Initialize the global variables.
sr = 44100
kr = 4410
ksmps = 10
nchnls = 1

; Instrument #1.
instr 1
  i1 = log(8)
  print i1
endin


</CsInstruments>
<CsScore>

; Play Instrument #1 for one second.
i 1 0 1
e


</CsScore>
</CsoundSynthesizer>

Its output should include a line like this:

instr 1:  i1 = 2.079

See also

Mathematical Functions

Credits

Written by John ffitch.

New in version 3.47

Example written by Kevin Conder.