Precision

Limitations on precision, effects of rounding and padding

Computer words consist of a finite number of bits. This means that the binary encoding of variables is only an approximation of an arbitrarily precise real-world value. Therefore, the limitations of the binary representation automatically introduce limitations on the precision of the value.

Topics

Range and Precision
Range and precision of fixed-point data types.
Maximize Precision
To maximize precision, make the slope as small as possible while keeping the range adequately large.
Rounding

Rounding involves going from high precision to lower precision and produces quantization errors and computational noise.
- Rounding Mode: Ceiling
- Rounding Mode: Convergent
- Rounding Mode: Floor
- Rounding Mode: Nearest
- Rounding Mode: Round
- Rounding Mode: Simplest
- Rounding Mode: Zero
Rounding Modes for Fixed-Point Simulink Blocks
Fixed-point Simulink^® blocks support seven different rounding modes.
Net Slope and Net Bias Precision
Net slope and bias precision, detecting precision loss, underflow, and overflow.
Detect Fixed-Point Constant Precision Loss
This example shows how to detect fixed-point constant precision loss.
Use Scaled Doubles to Avoid Precision Loss
How to avoid precision loss by overriding the data types in your model with scaled doubles.

Featured Examples

Compute Quantization Error

Compute and compare the statistics of the signal quantization error when using various rounding methods.

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