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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def tlog_inv(y, th=1, r=_display_max, d=_l_mmax):
 """ Inverse truncated log10 transform. Values Parameters y : num | num iterable values to be transformed. th : num Inverse values below th are transormed to th. Must be > positive. r : num (default = 10**4) maximal transformed value. d : num (default = log10(2**18)) log10 of maximal possible measured value. tlog_inv(r) = 10**d Returns ------- Array of transformed values. """

    if th <= 0:
        raise ValueError('Threshold value must be positive. %s given.' % th)
    x = 10 ** (y * 1. * d / r)
    try:
        x[x < th] = th
    except TypeError:
        if x < th: x = th
    return x