The Alternative Csound Reference Manual
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# GEN19

GEN19 -- Generate composite waveforms made up of weighted sums of simple sinusoids.

## Description

These subroutines generate composite waveforms made up of weighted sums of simple sinusoids. The specification of each contributing partial requires 4 p-fields using GEN19.

## Syntax

f # time size 19 pna stra phsa dcoa pnb strb phsb dcob ...

## Initialization

size -- number of points in the table. Must be a power of 2 or power-of-2 plus 1 (see f statement).

pna, pnb, etc. -- partial no. (relative to a fundamental that would occupy size locations per cycle) of sinusoid a, sinusoid b, etc. Must be positive, but need not be a whole number, i.e., non-harmonic partials are permitted. Partials may be in any order.

stra, strb, etc. -- strength of partials pna, pnb, etc. These are relative strengths, since the composite waveform may be rescaled later. Negative values are permitted and imply a 180 degree phase shift.

phsa, phsb, etc. -- initial phase of partials pna, pnb, etc., expressed in degrees.

dcoa, dcob, etc. -- DC offset of partials pna, pnb, etc. This is applied after strength scaling, i.e. a value of 2 will lift a 2-strength sinusoid from range [-2,2] to range [0,4] (before later rescaling).

| Note

- These subroutines generate stored functions as sums of sinusoids of different frequencies. The two major restrictions on GEN10 that the partials be harmonic and in phase do not apply to GEN09 or GEN19.

  In each case the composite wave, once drawn, is then rescaled to unity if p4 was positive. A negative p4 will cause rescaling to be skipped.

## Examples

    f    2    0    1024     19    .5   1    270    1

This example creates a rising sigmoid [0 - 2]. It will be rescaled.

## See Also

GEN09, GEN10

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