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Some test for Top-hat filter

1. Peak standard deviation:
    Set the peak std for 1, 2.5, 5, 10 and 20. After std=10, the signals are difficult to identify.


2. Noise:
    Set different noise for 0%, 25%, 50%, 75% and 100%. The peaks are hard to identify from 75% noise.
3. Different THF signal window:
    Set the noise to 100% and use the different signal window to identify the signal. The result shows the wider window can improve the peak identification.

 Summary:
The THF can help us to identify the weak signal from the high exponential background. It is noted that the S/N ratio would affect the THF result. If we want to identify the rare element in the material, we may use the high S/N ratio spectrum for applying THF or using the large signal window for noisy data.
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