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Detect underflow

Specifies diagnostic action to take when a fixed-point constant underflow occurs during simulation.


Select the diagnostic action to take if Simulink® software detects a 32-bit integer value was converted to a floating-point value.

Category: Diagnostics


Default: none


Simulink software takes no action.


Simulink software displays a warning.


Simulink software terminates the simulation and displays an error message.


  • This diagnostic applies only to fixed-point constants (net slope and net bias).

  • Fixed-point constant underflow occurs when Simulink software encounters a fixed-point constant whose data type does not have enough precision to represent the ideal value of the constant because the ideal value is too small.

  • When fixed-point constant underflow occurs, casting the ideal value to the data type causes the value of the fixed-point constant to become zero, and therefore to differ from its ideal value.


This parameter requires a Fixed-Point Designer™ license.

Command-Line Information

Value: 'none' | 'warning' | 'error'
Default: 'none'

Recommended Settings

DebuggingNo impact
TraceabilityNo impact
EfficiencyNo impact
Safety precautionNo impact

Related Topics