Topics

One may apply to musical classes oper ators such as addition. In this case, adding a note to another note must be user defined. This will require to redefine a method starting from a user's generic function. In our case, we will start from our generic function myplus already defined in tutorial 42 and build new methods for NOTE and CHORD musical classes.

Functions used

x-append, sort., remove-dup, NOTE and CHORD.

We will define the addition operation for the NOTE class as adding up two notes. This will construct an interval. In order to do that we will use musical classes that you will find in the 'packages' folder on your workspace. The musical classes are found in the 'music -> score' subfolders.

• Drag myplus function onto a patch and double click on its icon in order to open the methods window and add a new method as we have already done in tutorial 42.

• In the new window, we will add two inputs and one output. Drag the NOTE class from the package music->score on both inputs. There we will notice that the new inputs have many outputs. These refer to the slots of our class.

 

If we open the NOTE class in the packages folder we will see these slots and their data type

 

The first slot is always 'self' and represents the object (class) itself. There we can access all data contained in the note. The self slot doesn't appear in the packaged representation because it is always present it most of the classes.

 

Further, there are some "hidden" slots that we cannot see in the graphical representation of these classes. In our example above it is the 'tie' slot. So, the extra outputs stand respectively as follows:

• self (the object itself)
• midic (an integer)
• vel (an integer)
• dur (an integer)
• chan (an integer)

 

 

• In order to construct an interval we will append midic from both inputs, using the second output of each

• Now we must decide wether we will output a list of midics or better, an instance of a class (returning a CHORD object). We will choose the second solution, and so we will connect the output of x-append to the second input of a CHORD factory. Then we will connect the first output of CHORD to our output of our method.

• Now we may use our newly edited method as follows:
  • Connect the first input of two NOTEs factory to myplus.
  • myplus will append midics notes of both factory
  • Connect the output of myplus to the first input 'self' of a CHORD.
  • The resulting CHORD factory will show the constructed interval

We will now edit a new method for CHORDs . This method will concatenate two CHORDs into a single one, without any repretition of the same note and will sort all notes starting from the lowest pitch to the highest.

 

• We will first open a new method window and drag two CHORD classes onto both inputs as we have already done for the NOTE method

 

• We will connect the second slot (list of midics)of both inputs to x-append
• Connect x-append to sort. This will sort the newly concatenated list in an increasing order of midics
• Connect sort. to remove-dup in order to remove duplicates
• We will then connect the output of remove-dup to the second input <lmidic> of CHORD.
• The <self> output of CHORD is connected to the output of our new method

 

 

We will use this method as follows:

 

 

Two CHORDs factory are connected to myplus

• First CHORD:

 

• Second CHORD:

You may notice that these two CHORDs have one common note: D sharp

• The reulting CHORD in 'order' mode will be :