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Fixed Point

Represent signals and parameter values with fixed-point numbers to improve performance of generated code

Within digital hardware, numbers are represented as either fixed-point or floating-point data types. For both of these data types, word sizes are fixed at a set number of bits. However, the dynamic range of fixed-point values is much less than floating-point values with equivalent word sizes. While floating-point processors can greatly simplify the real-time implementation of a system, and effectively approximate real-world numbers, fixed-point processors carry numerous other benefits. Fixed-point processors are generally smaller, consuming less power. They also require less memory and less processor time to perform.

To simulate a model that uses fixed-point numbers, you must install the Fixed-Point Designer™ product. You do not need the Fixed-Point Designer product to edit a model containing fixed-point blocks, or to specify fixed-point data types.

Functions

fxptdlg Start Fixed-Point Tool
fixdt Create Simulink.NumericType object describing fixed-point or floating-point data type
fixpt_look1_func_approx Optimize fixed-point approximation of nonlinear function by interpolating lookup table data points
fixpt_evenspace_cleanup Modify breakpoints of lookup table to have even spacing
fixpt_interp1 Implement 1-D lookup table
fixpt_look1_func_plot Plot fixed-point approximation function for lookup table
fixpt_set_all Set property for each fixed-point block in subsystem
fixptbestexp Exponent that gives best precision for fixed-point representation of value
fixptbestprec Determine maximum precision available for fixed-point representation of value
float Create Simulink.NumericType object describing floating-point data type
num2fixpt Convert number to nearest value representable by specified fixed-point data type
sfix Create Simulink.NumericType object describing signed fixed-point data type

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