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# powoftwo

powoftwo -- Performs a power-of-two calculation.

## Description

Performs a power-of-two calculation.

## Syntax

powoftwo(x) (init-rate or control-rate args only)

## Performance

powoftwo() function returns 2 ^ x and allows positive and negatives numbers as argument. The range of values admitted in powoftwo() is -5 to +5 allowing a precision more fine than one cent in a range of ten octaves. If a greater range of values is required, use the slower opcode pow.

These functions are fast, because they read values stored in tables. Also they are very useful when working with tuning ratios. They work at i- and k-rate.

## Examples

Here is an example of the powoftwo opcode. It uses the files powoftwo.orc and powoftwo.sco.

Example 1. Example of the powoftwo opcode.

    /* powoftwo.orc */
    ; Initialize the global variables.
    sr = 44100
    kr = 4410
    ksmps = 10
    nchnls = 1

    ; Instrument #1.
    instr 1
      i1 = powoftwo(12)
      print i1
    endin
    /* powoftwo.orc */

    /* powoftwo.sco */
    ; Play Instrument #1 for one second.
    i 1 0 1
    e
    /* powoftwo.sco */

Its output should include a line like this:

    instr 1:  i1 = 4096.000

## See Also

logbtwo, pow

## Credits

Author: Gabriel Maldonado
Italy
June 1998

Author: John ffitch
University of Bath, Codemist, Ltd.
Bath, UK
July 1999

Example written by Kevin Conder.

New in Csound version 3.57

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