Source code for cr.sparse._src.geo.wavelets

# Copyright 2021 CR-Suite Development Team
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# Licensed under the Apache License, Version 2.0 (the "License");
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"""
Wavelets popular in geophysics literature
"""

import jax.numpy as jnp

def ricker(t, f0=10):
    """
    Returns the Ricker wavelet for a given peak frequency at specified times.

    There are several different ways in which the Ricker wavelet can be 
    defined.

    Here we are interested in the definition popular in seismology.
    
    See https://subsurfwiki.org/wiki/Ricker_wavelet for details.
    """
    w = (1 - 2 * (jnp.pi * f0 * t) ** 2) * jnp.exp(-(jnp.pi * f0 * t) ** 2)
    return w