Hello everybody!

Today i stumbled uppon the ptable opcode, which i never saw yet.

Where is the difference to the table opcode?

Greetings,
Philipp

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Off the top of my head. Some internal diffs, table uses integer code to handle wraparound if table pow of two size, ptable always uses floating-point maths.

Before 6.0 table could not handle non-pow of two tables. So instead of fixing it, ptable was introduced (same for poscil etc). Not the best decision imho but so it goes.


Prof. Victor Lazzarini
Maynooth University
Ireland

> On 23 Jan 2026, at 07:09, Philipp Neumann <0000119f78f3a4f9-dmarc-request@listserv.heanet.ie> wrote:
> 
> Hello everybody!
> 
> Today i stumbled uppon the ptable opcode, which i never saw yet.
> 
> Where is the difference to the table opcode?
> 
> Greetings,
> Philipp
> 
> Csound mailing list
> Csound@listserv.heanet.ie
> https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND
> Send bugs reports to
>        https://github.com/csound/csound/issues
> Discussions of bugs and features can be posted here

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There is a subtle difference still - poscil etc will never use integer maths. In some edge cases (a combination of floats build and
large tables), they are more precise (hence the ‘p’).

> On 23 Jan 2026, at 10:01, Rory Walsh  wrote:
> 
> If there is no longer any advantage to using it, or poscil for that matter, should they be marked deprecated? 
> 
> On Fri, 23 Jan 2026 at 07:16, vlz  wrote:
> Off the top of my head. Some internal diffs, table uses integer code to handle wraparound if table pow of two size, ptable always uses floating-point maths.
> 
> Before 6.0 table could not handle non-pow of two tables. So instead of fixing it, ptable was introduced (same for poscil etc). Not the best decision imho but so it goes.
> 
> 
> Prof. Victor Lazzarini
> Maynooth University
> Ireland
> 
> > On 23 Jan 2026, at 07:09, Philipp Neumann <0000119f78f3a4f9-dmarc-request@listserv.heanet.ie> wrote:
> > 
> > Hello everybody!
> > 
> > Today i stumbled uppon the ptable opcode, which i never saw yet.
> > 
> > Where is the difference to the table opcode?
> > 
> > Greetings,
> > Philipp
> > 
> > Csound mailing list
> > Csound@listserv.heanet.ie
> > https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND
> > Send bugs reports to
> >        https://github.com/csound/csound/issues
> > Discussions of bugs and features can be posted here
> 
> Csound mailing list
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> https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND
> Send bugs reports to
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> Csound mailing list Csound@listserv.heanet.ie https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND Send bugs reports to https://github.com/csound/csound/issues Discussions of bugs and features can be posted here

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yes i once did a test which i think is still valid, resulting in poscil 
is more precise.
by the way, i don't find ptable at 
https://csound.com/manual/reference/opcodesReference/

On 23/01/2026 12:34, vlz wrote:
> There is a subtle difference still - poscil etc will never use integer maths. In some edge cases (a combination of floats build and
> large tables), they are more precise (hence the ‘p’).
> 
>> On 23 Jan 2026, at 10:01, Rory Walsh  wrote:
>>
>> If there is no longer any advantage to using it, or poscil for that matter, should they be marked deprecated?
>>
>> On Fri, 23 Jan 2026 at 07:16, vlz  wrote:
>> Off the top of my head. Some internal diffs, table uses integer code to handle wraparound if table pow of two size, ptable always uses floating-point maths.
>>
>> Before 6.0 table could not handle non-pow of two tables. So instead of fixing it, ptable was introduced (same for poscil etc). Not the best decision imho but so it goes.
>>
>>
>> Prof. Victor Lazzarini
>> Maynooth University
>> Ireland
>>
>>> On 23 Jan 2026, at 07:09, Philipp Neumann <0000119f78f3a4f9-dmarc-request@listserv.heanet.ie> wrote:
>>>
>>> Hello everybody!
>>>
>>> Today i stumbled uppon the ptable opcode, which i never saw yet.
>>>
>>> Where is the difference to the table opcode?
>>>
>>> Greetings,
>>> Philipp
>>>
>>> Csound mailing list
>>> Csound@listserv.heanet.ie
>>> https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND
>>> Send bugs reports to
>>>         https://github.com/csound/csound/issues
>>> Discussions of bugs and features can be posted here
>>
>> Csound mailing list
>> Csound@listserv.heanet.ie
>> https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND
>> Send bugs reports to
>>          https://github.com/csound/csound/issues
>> Discussions of bugs and features can be posted here
>> Csound mailing list Csound@listserv.heanet.ie https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND Send bugs reports to https://github.com/csound/csound/issues Discussions of bugs and features can be posted here
> 
> Csound mailing list
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Thanks for clarifying!

> Am 23.01.2026 um 14:56 schrieb joachim heintz :
> 
> yes i once did a test which i think is still valid, resulting in poscil is more precise.
> by the way, i don't find ptable at https://csound.com/manual/reference/opcodesReference/
> 
>> On 23/01/2026 12:34, vlz wrote:
>> There is a subtle difference still - poscil etc will never use integer maths. In some edge cases (a combination of floats build and
>> large tables), they are more precise (hence the ‘p’).
>>>> On 23 Jan 2026, at 10:01, Rory Walsh  wrote:
>>> 
>>> If there is no longer any advantage to using it, or poscil for that matter, should they be marked deprecated?
>>> 
>>>> On Fri, 23 Jan 2026 at 07:16, vlz  wrote:
>>> Off the top of my head. Some internal diffs, table uses integer code to handle wraparound if table pow of two size, ptable always uses floating-point maths.
>>> 
>>> Before 6.0 table could not handle non-pow of two tables. So instead of fixing it, ptable was introduced (same for poscil etc). Not the best decision imho but so it goes.
>>> 
>>> 
>>> Prof. Victor Lazzarini
>>> Maynooth University
>>> Ireland
>>> 
>>>> On 23 Jan 2026, at 07:09, Philipp Neumann <0000119f78f3a4f9-dmarc-request@listserv.heanet.ie> wrote:
>>>> 
>>>> Hello everybody!
>>>> 
>>>> Today i stumbled uppon the ptable opcode, which i never saw yet.
>>>> 
>>>> Where is the difference to the table opcode?
>>>> 
>>>> Greetings,
>>>> Philipp
>>>> 
>>>> Csound mailing list
>>>> Csound@listserv.heanet.ie
>>>> https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND
>>>> Send bugs reports to
>>>>        https://github.com/csound/csound/issues
>>>> Discussions of bugs and features can be posted here
>>> 
>>> Csound mailing list
>>> Csound@listserv.heanet.ie
>>> https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND
>>> Send bugs reports to
>>>         https://github.com/csound/csound/issues
>>> Discussions of bugs and features can be posted here
>>> Csound mailing list Csound@listserv.heanet.ie https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND Send bugs reports to https://github.com/csound/csound/issues Discussions of bugs and features can be posted here
>> Csound mailing list
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>> Send bugs reports to
>>         https://github.com/csound/csound/issues
>> Discussions of bugs and features can be posted here
> 
> Csound mailing list
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> 

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