array.expr
Evaluate a math expression for an array
Description
Performs mathematical calculations using C language-style mathematical operations. Operates on inputs that are arrays rather than collections of single values.
Arguments
expression[list]
optional
The argument to the vexpr object is a mathematical expression composed of numbers, arithmetic operators such as + or *, comparisons such as < or > , C functions such as min () or pow () , names of table objects, and changeable arguments ( $i , $f , and $s ) for ints, floats, and symbols received in the inlets.
constant[number]
optional
Numbers can be used as constants in the mathematical expression.
format[symbol]
optional
Changeable arguments that specify data formats associated with an inlet are described using a combination of a data type ( $i or $f ) and an inlet number (example: $i2 ). The argument will be replaced by numbers received in the specified inlet.
table[symbol]
optional
Changeable arguments that specify accessing data from a table are described using the argument $s and an inlet number which is replaced by the name of a table to be accessed. The argument should be immediately followed by a number in brackets specifying an address in the table. (Examples: $s2[7] or $s3[$i1] .)
(other)[symbol]
optional
The vexpr object understands the following arithmetic operators: + , - , * , / , %. Other operators are ~ (one's complement), ^ (bitwise exclusive or), & , && , | , || , and ! (not).
Many C language math functions can be understood by vexpr. A function must be followed immediately by parentheses containing any arguments necessary to the function. If the function requires a comma between arguments, the comma must be preceded by a backslash ( \ ) so that Max will not be confused by it. For example: (pow ($i1\,2) + $f2) .
C language functions understood by vexpr are: abs, min, max, sin, cos, tan, asin, acos, atan, atan2, sinh, cosh, tanh, int (convert to integer), float (convert to float), pow, sqrt, fact (factorial), exp (power of e to x), log10 (log), ln or log (natural log), and random. Additional functions can be added by means of external code resources placed in Max's startup folder.
The array.expr also understands the special function arrayidx() (no arguments) which provides an int representing the current array index being processed.
Attributes
fillmode[int]: 0
The fillmode determines how to resize arrays which don't match the length of the array sent into the left inlet. Several options are available.
Possible values:
0 = 'Repeat'
(
Repeat elements
)
All elements of the array will be repeated to reach the required length. If the incoming left-inlet array has a length of 3, the array [ 2 ] would become [ 2, 2, 2 ] ; [ 2 1 ] would become [ 2 1 2 ] .
1 = 'Repeat Last'
(
Repeat the last element
)
The last element of the array will be repeated to reach the required length. If the incoming left-inlet array has a length of 3, the array [ 2 ] would become [ 2, 2, 2 ] ; [ 2, 1 ] would become [ 2, 1, 1 ] .
2 = 'Repeat Zero'
(
Repeat zero
)
The integer 0 will be repeated to reach the required length. If the incoming left-inlet array has a length of 3, the array [ 2 ] would become [ 2, 0, 0 ] ; [ 2, 1 ] would become [ 2, 1, 0 ] .
3 = 'Interpolate (Linear)'
(
Linear-interpolate
)
Linear interpolation will be performed on the array to reach the required length. If the incoming left-inlet array has a length of 3, the array [ 1, 3 ] would become [ 1, 2, 3 ] ; [ 5, 1 ] would become [ 5, 3, 1 ] . If all elements are ints , the interpolation will be performed using integers; if any element is a float , the interpolation will return floating-point numbers.
Common Box Attributes
annotation[symbol]
Sets the text that will be displayed in the Clue window when the user moves the mouse over the object.
background[int]: 0
Adds or removes the object from the patcher's background layer. background 1 adds the object to the background layer, background 0 removes it. Objects in the background layer are shown behind all objects in the default foreground layer.
color[4 floats]
Sets the color for the object box outline.
fontface[int]
Sets the type style used by the object. The options are:
plain
bold
italic
bold italic
Possible values:
0 = 'regular'
1 = 'bold'
2 = 'italic'
3 = 'bold italic'
fontname[symbol]
Sets the object's font.
fontsize[float]
Sets the object's font size (in points).
Possible values:
'8'
'9'
'10'
'11'
'12'
'13'
'14'
'16'
'18'
'20'
'24'
'30'
'36'
'48'
'64'
'72'
hint[symbol]
Sets the text that will be displayed in as a pop-up hint when the user moves the mouse over the object in a locked patcher.
ignoreclick[int]: 0
Toggles whether an object ignores mouse clicks in a locked patcher.
jspainterfile[symbol]
You can override the default appearance of a user interface object by assigning a JavaScript file with code for painting the object. The file must be in the search path.
patching_rect[4 floats]: 0. 0. 100. 0.
Aliases: patching_position, patching_size
Sets the position and size of the object in the patcher window.
position[2 floats]
write-only
Sets the object's x and y position in both patching and presentation modes (if the object belongs to its patcher's presentation), leaving its size unchanged.
presentation[int]: 0
Sets whether an object belongs to the patcher's presentation.
presentation_rect[4 floats]: 0. 0. 0. 0.
Aliases: presentation_position, presentation_size
Sets the x and y position and width and height of the object in the patcher's presentation, leaving its patching position unchanged.
rect[4 floats]
write-only
Sets the x and y position and width and height of the object in both patching and presentation modes (if the object belongs to its patcher's presentation).
size[2 floats]
write-only
Sets the object's width and height in both patching and presentation modes (if the object belongs to its patcher's presentation), leaving its position unchanged.
textcolor[4 floats]
Sets the color for the object's text in RGBA format.
textjustification[int]
Sets the justification for the object's text.
Possible values:
0 = 'left'
1 = 'center'
2 = 'right'
valuepopup[int]: 0
For objects with single values, enabling valuepopup will display the object's current value in a popup caption when the mouse is over the object or it is being changed with the mouse.
valuepopuplabel[int]: 0
Sets the source of a text label shown in a value popup caption.
Possible values:
0 = 'None'
1 = 'Hint'
2 = 'Scripting Name'
3 = 'Parameter Long Name'
4 = 'Parameter Short Name'
varname[symbol]
Sets the patcher's scripting name, which can be used to address the object by name in pattr, scripting messages to thispatcher, and the js object.
Messages
bang
Reprocess previously received arrays and trigger output.
int
Convert an incoming integer to an array, then process as described for the array message.
- value
[int]
float
Convert an incoming floating-point number to an array, then process as described for the array message.
- value
[float]
list
Convert an incoming list to an array, then process as described for the array message.
- list-value
[list]
anything
Convert an incoming list to an array, then process as described for the array message.
- list-value
[list]
array
The elements of each array are used individually, in order from left to right, to replace the changeable argument in a series of evaluations of the expression. When an array is received in the left inlet, the expression is first evaluated using the first element of each array, then using the second element of each array, etc. The series of results of these evaluations is then sent out as a array.
If the arrays are not of the same length, the fillmode will be used to determine how to handle the length discrepancy.
dictionary
Wrap an incoming dictionary object in an array, then process as described for the array message.
- dictionary-value
[list]
string
Wrap a string object in an array, then process as described for the array message.
- string-value
[list]
See Also
| Name | Description |
|---|---|
| array | Create or duplicate an array object |
| array.fill | Generate an array of a specified length |
| expr | Evaluate a mathematical expression |
| vexpr | Evaluate a math expression for a list |