# scale

## Description

The scale object maps an input range of float or integer values to an output range. The output range can be larger or smaller than the input range, can be inverted and can change numeric type. If specified, the mapping can also be exponential.

## Examples

## Arguments

### input-low [number]

Sets the low end of the expected input range. Incoming values are not clipped to this range; rather, the input range is used to determine the value mapping formula.

### input-high [number]

Sets the high end of the expected input range. Incoming values are not clipped to this range; rather, the input range is used to determine the value mapping formula.

### output-low [number]

This sets the low end of the output range, and will be the lowest output value if the input value stays with its expected range.

### output-high [number]

This sets the high end of the output range, and will be the highest output value if the input value stays with its expected range.

### exponential [float]

This optional fifth argument specifies the nature of the scaling curve. This argument must be a floating-point number greater than 1., with larger values leading to steeper exponential curves.

In classic mode a typical value for this argument is 1.06. The object does its actual scaling after the exponential calculation, and the number is converted according to the following expression:

(out_high-out_low >= 0) ? (out_low + (out_high-out_low) * ( (out_high - out_low) * exp(-1*(in_high-in_low)*log(power)) * exp(x*log(power)) )) : (-1) * ( out_low + (out_high-out_low) * ( (out_high - out_low) * exp(-1*(in_high-in_low)*log(power)) * exp(x*log(power)) ) )

In non- classic (modern) mode the value for the scaling curve must be higher than 0. and is converted according to the following expression:

((x-in_low)/(in_high-in_low) == 0) ? out_low : (((x-in_low)/(in_high-in_low)) > 0) ? (out_low + (out_high-out_low) * ((x-in_low)/(in_high-in_low))^exp) : ( out_low + (out_high-out_low) * -((((-x+in_low)/(in_high-in_low)))^(exp)))

Note that prior to Max 6.0.4 the exponent was inverted. Thus, if you gave it an exponent of 2 the object behaved like it had an exponent of 0.5, and if you gave it an exponent of 0.5 it behaved like it had an exponent of 2. Patches from versions prior to 6.0.4 may require updating to work properly.

## Attributes

### classic [int]

Classic mode uses exponential function that is backward compatible with old IRCAM patchers.

### Common Box Attributes

## Messages

### bang

### int

#### Arguments

### float

#### Arguments

In second inlet: Sets the low end of the input range.

In third inlet: Sets the high end of the input range.

In fourth inlet: Sets the low end of the output range.

In fifth inlet: Sets the high end of the output range.

In sixth inlet: Sets the scaling curve value as described in the object arguments section.

### list

#### Arguments

## Output

### float

When scale receives a value in its leftmost inlet, that value is scaled to the indicated output range of values.

### int

If only four arguments are provided and all four are of type

, scale will output scaled values as integers. Otherwise output is floating-point.## See Also

Name | Description |
---|---|

expr | |

linedrive | |

zmap | |

Max Basic Tutorial 11: Procedural Drawing | Max Basic Tutorial 11: Procedural Drawing |