SoftMax

Gradual approach of a floor below which output can never fall

Diagram

Information

The output y is obtained as a smooth maximum with regard to the inputs u and u_min:

Formula.svg

The following graph shows the results for u_min = 1.0 and k ∈ {10,5,3,2}:

Graph for u_min = 1.0
Graph.svg

Notes

  • The soft maximum is a special case of the generalized f-mean.

See also

SoftMin

Parameters (2)

k

Value: 4.7

Type: Real

Description: Parameter to control the closeness to a hard maximum

useMaxOperator

Value: false

Type: Boolean

Description: = true, if a regular 'hard' maximum is to be used

Connectors (3)

y

Type: RealOutput

Description: Output signal

u

Type: RealInput

Description: Input

u_min

Type: RealInput

Description: The floor

Components (13)

u_min_shifted

Type: Gap

Description: Compare goal (u1) and current value (u2) to determine gap

u_shifted

Type: Gap

Description: Compare goal (u1) and current value (u2) to determine gap

switch

Type: Switch

Description: Switching between inputs depending upon condition

useHardMaxQ

Type: ConstantConverterBoolean

Description: A constant boolean value is turned into a constant signal

softmin_shifted

Type: Add_2

Description: Sum of two inputs

hardMax

Type: Max

Description: Hard max operator

scaledInput

Type: Gain

Description: Input is multiplied by constant parameter

expInput

Type: Exp

Description: Natural exponential function

sumExp

Type: Add_2

Description: Sum of two inputs

logSum

Type: Log

Description: Logarithm of the input to a given base

adjustmentFactor

Type: Gain

Description: Input is multiplied by constant parameter

expMin

Type: Exp

Description: Natural exponential function

scaledMin

Type: Gain

Description: Input is multiplied by constant parameter

Revisions

  • Introduced in v2.0.0.

  • Fixed hardMax and numerical stability issues in v2.1.0.