Topic: Inversion? (Read 18248 times)

## Inversion?

##### 2007-04-20 05:51 pm
Greetings,

I seem to remember  a user tool (I thought it was Global Mod) allowing one to invert a selection of notes.  I know I'm not thinking of the retrograde tool, but something that inverted.  Is my memory bad, or my imagination too good?

Robin

## Re: Inversion?

##### Reply #1 – 2007-04-20 06:55 pm
I also remember reading about an Inversion tool but I have not found it (or any evidence of it) anywhere.  Maybe someone was thinking of creating one but hasn't completed it yet.  I have not found any evidence of that thread either...

## Re: Inversion?

##### Reply #2 – 2007-04-20 11:43 pm
What do you want the tool to do? Invert a melody line around a given note or invert a chord?
Registered user since 1996

## Re: Inversion?

##### Reply #3 – 2007-04-21 12:13 am
I remember a command line for Global Mod being shown as an example at one stage - don't remember where but it basically multiplied the Pos by -1...

Note Pos*=-1

This will invert around the centre line of the staff, 'B' on a treble staff...  If you want to invert around another note you need to be a little more creative...

Easiest way I can think of is to move everything up or down till the centre line is the middle of the inversion you want, multiply by -1 and reposition the selection back to where it started...

E.G if you wanted to invert around a treble D, lower everything by '2', multiply by '-1' and move everything back up by '2'

Note Pos-=2 Note Pos*=-1 Note Pos+=2

Note that case and spaces are significant!

Chords will take a little more thought...
I plays 'Bones, crumpets, coronets, floosgals 'n youfonymums - 'n I'm lernin' tubies now too

## Re: Inversion?

##### Reply #4 – 2007-04-21 02:01 am
On the Scritporium http://nwc-scriptorium.org/helpful.html
The is a utility of mine MIDIExp which can Invert, mirror and pitch expand around a given note.
It's a DOS program for QBasic but there is an exe file converted by the Late Fred Nachbaur that will run stand alone (with BRUN45 support).
It require a MIDI file exported from NWC as the inout file for conversion.
Because it's DOS the file name cannot exceed 8 characters.

## Re: Inversion?

##### Reply #5 – 2007-04-21 02:22 am
I remember a command line for Global Mod being shown as an example at one stage - don't remember where but it basically multiplied the Pos by -1...[snip]
Chords will take a little more thought...
Global Mod should cover simple melodies. I gave the chords a little thought, see: Chord Inversion Tool
Registered user since 1996

## Re: Inversion?

##### Reply #6 – 2007-04-21 02:16 pm
I remember using a tool that did inversions, and I am sure that it was in an earlier incarnation of Global Mod.  This would be some time ago (a year, year and a half), but I do remember it.

## Re: Inversion?

##### Reply #7 – 2007-04-21 03:21 pm
G'day Robin,

I remember using a tool that did inversions, and I am sure that it was in an earlier incarnation of Global Mod.  This would be some time ago (a year, year and a half), but I do remember it.

My reply (3) above gives examples of the Global Mod commands required...  They work, I tested before posting.
I plays 'Bones, crumpets, coronets, floosgals 'n youfonymums - 'n I'm lernin' tubies now too

## Re: Inversion?

##### Reply #8 – 2007-04-21 06:49 pm
Lawrie,

Thanks.  I'll give it a go.  Not today, though, as I'm feeling rotten (some sort of virus has me by the throat).

Robin

## Re: Inversion?

##### Reply #9 – 2007-04-23 03:37 pm
Lawrie,

Feeling better.  And, it worked with charm-like perfection.  Thanks, mate.

Robin

## Re: Inversion?

##### Reply #10 – 2007-04-23 09:11 pm
G'day Robin,
glad you're feeling better, and glad the Global Mod stuff was what you needed.

Lawrie
I plays 'Bones, crumpets, coronets, floosgals 'n youfonymums - 'n I'm lernin' tubies now too