Log10 HDL Optimized

R2026b

Compute base-10 logarithm of input

Since R2026b

• 

Log10 HDL Optimized block

To add a block to a model, double-click the canvas and start typing the block name. Then, select the block from the list.

Libraries:
Fixed-Point Designer HDL Support / Math Operations

Description

The Log10 HDL Optimized block computes the base-10 logarithm of an input. This block is optimized for efficient HDL code generation with HDL Coder™.

Ports

Input

u — Value to compute base-10 logarithm of

real-valued scalar | vector | matrix

Value to compute base-10 logarithm of, specified as a real-valued scalar, vector, or matrix. Fixed-point inputs must use binary-point scaling.

Data Types: single | double | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | fixed point

validIn — Whether input is valid

scalar

Whether input is valid, specified as a Boolean scalar. This control signal indicates when the data from the u input port is valid. When this value is 1 (true), the block captures the value at the u input port. When this value is 0 (false), the block ignores the input samples.

Data Types: Boolean

Output

log₁₀u — Base-10 logarithm of input

scalar | vector | matrix

Base-10 logarithm of input, returned as a scalar, vector, or matrix the same size as the input u. For fixed-point inputs, the block returns a signed fixed-point data type. For floating-point inputs, the output data type is the same as the input data type.

Data Types: single | double | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | fixed point

validOut — Whether output data is valid

scalar

Whether output data is valid, returned as a Boolean scalar. When the value of this control signal is 1 (true), the block has successfully computed the output. When this value is 0 (false), the output data is not valid.

Data Types: Boolean

logZero — Whether value at output port is result of log10(0)

scalar | vector | matrix

Whether value at output port is the result of log10(0), returned as a Boolean scalar, vector, or matrix. When the value of this port is 1 (true), the block has processed an input value of 0. When the value of this port is 0 (false), the block has processed a nonzero input value.

Tips

When the value at the logZero port is 1 (true), the output saturates to the maximum that the output data type allows.

Dependencies

To enable this port, select the Show log zero port parameter.

Data Types: Boolean

Parameters

To edit block parameters interactively, use the Property Inspector. From the Simulink^® Toolstrip, on the Simulation tab, in the Prepare gallery, select Property Inspector.

Show log zero port — Whether block shows logZero port

on (default) | off

Whether the block shows the logZero port.

Programmatic Use

To set the block parameter value programmatically, use the set_param function.

To get the block parameter value programmatically, use the get_param function.

Parameter:	SignalLogZero
Values:	1or true (default) | 0 or false
Data Types:	logical

Example: set_param(gcb,SignalLogZero = 0)

Programmatic Use: Add Block

To add the block programmatically, use the add_block function with one of these library block paths as the source.

"embeddedMatrixLib/Math Operations/Log10 HDL Optimized"

Example: add_block("embeddedMatrixLib/Math Operations/Log10 HDL Optimized","myModel/myBlock",MakeNameUnique="on")

For information about programmatic access to individual block parameters, see the Programmatic Use section of parameter descriptions on this page.

Algorithms

Latency

The latency of the Log10 HDL Optimized block depends on the data type of the input. The latency is:

• 9 for unsigned integer and fixed-point data types

• 11 for signed integer, signed fixed-point, and floating-point data types

Extended Capabilities

HDL Code Generation
Generate VHDL, Verilog and SystemVerilog code for FPGA and ASIC designs using HDL Coder™.

Version History

Introduced in R2026b