import tensorflow as tf

# RooArgusBG argus("argus","Argus PDF",mes,m0,argpar) ;


def argus_pdf(m, m0, c, p=0.5):
    t = m / m0
    u = 1 - t * t
    argus_t_ge_1 = m * tf.pow(u, p) * tf.exp(c * u)
    return tf.maximum(tf.zeros_like(m), argus_t_ge_1, name="argus_pdf")


# // --- Construct signal+background PDF ---
# RooRealVar nsig("nsig","#signal events",200,0.,10000) ;
