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managed_components/espressif__esp-dsp/examples/basic_math/README.md

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+# Basic Math Example 
+
+(See the README.md file in the upper level 'examples' directory for more information about examples.)
+
+This example demonstrates how to use basic math functions from esp-dsp library. Example does the following steps:
+
+1. Initialize the library
+2. Initialize input signals with 1024 samples
+3. Apply window to input signal by standard C loop.
+4. Calculate FFT for 1024 complex samples and show the result
+5. Show results on the plots
+6. Apply window to input signal by basic math functions dsps_mul_f32 and dsps_mulc_f32.
+7. Calculate FFT for 1024 complex samples
+8. Show results on the plots
+
+## How to use example
+
+### Hardware required
+
+This example does not require any special hardware, and can be run on any common development board.
+
+### Configure the project
+
+Under Component Config ---> DSP Library ---> DSP Optimization, it's possible to choose either the optimized or ANSI implementation, to compare them.
+
+### Build and flash
+
+Build the project and flash it to the board, then run monitor tool to view serial output (replace PORT with serial port name):
+
+```
+idf.py -p PORT flash monitor
+```
+
+(To exit the serial monitor, type ``Ctrl-]``.)
+
+See the Getting Started Guide for full steps to configure and use ESP-IDF to build projects.
+
+## Example output
+
+Here is an typical example console output. 
+
+```bash
+I (132) main: *** Start Example. ***
+I (132) main: *** Multiply tone signal with Hann window by standard C loop. ***
+I (152) view: Data min[432] = -173.749878, Data max[205] = 23.849705
+ ________________________________________________________________
+0                         |                                      |
+1                         |                                      |
+2                         |                                      |
+3                         ||                                     |
+4                        | |                                     |
+5                       ||  |                                    |
+6                    |||     ||                                  |
+7               |||||          ||||                              |
+8|||||||||||||||                   ||||||                        |
+9                                        |||||||||||||||||||||||||
+ 0123456789012345678901234567890123456789012345678901234567890123
+I (162) view: Plot: Length=512, min=-120.000000, max=40.000000
+I (162) main: *** Multiply tone signal with Hann window by esp-dsp basic math functions. ***
+I (162) view: Data min[432] = -173.749878, Data max[205] = 23.849705
+ ________________________________________________________________
+0                         |                                      |
+1                         |                                      |
+2                         |                                      |
+3                         ||                                     |
+4                        | |                                     |
+5                       ||  |                                    |
+6                    |||     ||                                  |
+7               |||||          ||||                              |
+8|||||||||||||||                   ||||||                        |
+9                                        |||||||||||||||||||||||||
+ 0123456789012345678901234567890123456789012345678901234567890123
+I (172) view: Plot: Length=512, min=-120.000000, max=40.000000
+I (172) main: *** End Example. ***
+```