Example Applications

Several example applications are offered to demonstrate use of the lib_xs3_math APIs through actual, simple code examples.

Building Examples

After configuring the CMake project (with the BUILD_EXAMPLES enabled), all the examples can be built by using the make command within the build directory. Individual examples can be built using make EXAMPLE_NAME, where EXAMPLE_NAME is the example to build.

Running Examples

To run example EXAMPLE_NAME on the XCORE-AI-EXPLORER board, from the CMake build directory, run the following command after building:

xrun --xscope example/EXAMPLE_NAME/EXAMPLE_NAME.xe

To run the example using the xCore simulator instead, use:

xsim example/EXAMPLE_NAME/EXAMPLE_NAME.xe

bfp_demo

The purpose of this application is to demonstrate, through example, how the arithmetic functions of lib_xs3_math’s block floating-point API may be used.

In it, three 32-bit BFP vectors are allocated, initialized and filled with random data. Then several BFP operations are applied using those vectors as inputs and/or outputs.

The example only demonstrates the real 32-bit arithmetic BFP functions (that is, functions with names bfp_s32_*). The real 16-bit (bfp_s16_*), complex 32-bit (bfp_complex_s32_*) and complex 16-bit (bfp_complex_s16_*) functions all use very similar conventions as the real 32-bit functions.

vect_demo

The purpose of this application is to demonstrate, through example, how the arithmetic functions of lib_xs3_math’s low-level vector API may be used.

In general the low-level arithmetic API are the functions in this library whose names begin with xs3_vect_*, such as xs3_vect_s32_mul() for element-wise multiplication of 32-bit vectors, and xs3_vect_complex_s16_scale() for multiplying a complex 16-bit vector by a complex scalar.

We assume that where the low-level API is being used it is because some behavior other than the default behavior of the high-level block floating-point API is required. Given that, rather than showcasing the breadth of operations available, this example examines first how to achieve comparable behavior to the BFP API, and then ways in which that behavior can be modified.

fft_demo

The purpose of this application is to demonstrate, through example, how the FFT functions of lib_xs3_math’s block floating-point API may be used.

In this example we demonstrate each of the offered forward and inverse FFTs of the BFP API.

filter_demo

The purpose of this application is to demonstrate, through example, how the functions of lib_xs3_math’s filtering vector API may be used.

The filtering API currently supports three different filter types:

• 32-bit FIR Filter

• 16-bit FIR Filter

• 32-bit Biquad Filter

This example app presents simple demonstrations of how to use each of these filter types.