expr
Description
Evaluate an expression using a C-like language. Variables and operators are used to create output values.
Examples
Discussion
Use the expr object to perform mathematical calculations using C language-style mathematical operations. The object evaluates expressions that use the "variables" $i1-$i9 (the first to ninth inlets, taken as integers), $f1-$f9 (the inlets as floats) and $s1-$s9 (the inlets as symbols), and/or constants of the same types. The operators are +, -, *, /, &, |, &&, ||, !, ~, and ^, and you can also use a set of predefined mathematical and statistical functions. The list of functions in expr are as follows: min, max, int (convert to integer), float (convert to float), pow (power), sqrt (square root), exp (power of e to x), log10 (log), ln (natural log), log (nat. log), sin, cos, tan, asin (arcsin), acos, atan, atan2, sinh, cosh, tanh, fact (factorial), random, round, floor, ceil, size (size of a table), sum (sum of table contents), Sum (sum with boundaries), avg (of table contents), Avg (avg with boundaries), store (store into a table).
Arguments
expression [list]
The argument to the expr 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 $s) for ints, floats, and symbols received in the inlets.
constant [number]
Numbers can be used as constants in the mathematical expression.
inlet-format [symbol]
Changeable arguments that specify data formats associated with an inlet are described using a combination of a data type ($i or $f) and an inlet number (example: $i2). The argument will be replaced by numbers received in the specified inlet.
table-info [$s]
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]
The expr object understands the following arithmetic operators: +, -, *, /, %. Other operators are ~ (one's complement), ^ (bitwise exclusive or), &, &&, |, ||, and ! (not).
Attributes
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] (default: 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'
hidden [int] (default: 0)
Toggles whether an object is hidden when the patcher is locked.
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] (default: 0)
Toggles whether an object ignores mouse clicks in a locked patcher.
jspainterfile [symbol]
JS Painter File
patching_rect [4 floats] (default: 0. 0. 100. 0.)
Sets the position and size of the object in the patcher window.
position [2 floats]
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] (default: 0)
Sets whether an object belongs to the patcher's presentation.
presentation_rect [4 floats] (default: 0. 0. 0. 0.)
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]
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]
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'
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
int
Arguments
(inlet1)
Arguments
(inlet2)
Arguments
(inlet3)
Arguments
(inlet4)
Arguments
(inlet5)
Arguments
(inlet6)
Arguments
(inlet7)
Arguments
(inlet8)
Arguments
(inlet9)
Arguments
float
Arguments
(inlet1)
Arguments
(inlet2)
Arguments
(inlet3)
Arguments
(inlet4)
Arguments
(inlet5)
Arguments
(inlet6)
Arguments
(inlet7)
Arguments
(inlet8)
Arguments
(inlet9)
Arguments
set
Arguments
sm1
Arguments
sm2
Arguments
sm3
Arguments
sm4
Arguments
sm5
Arguments
sm6
Arguments
sm7
Arguments
sm8
Arguments
sm9
Arguments
symbol
Arguments
list
Arguments
Output
float
The output is the result of the evaluated expression.
int
The output is the result of the evaluated expression.
See Also
| Name | Description |
|---|---|
| Working with Video in Jitter | Working with Video in Jitter |
| Gen | Gen |
| if | Conditional statement in if/then/else form |
| vexpr | Evaluate a math expression for a list |
| round | Round to a value |
| Max Basic Tutorial 22: Designing Equations | Max Basic Tutorial 22: Designing Equations |