cdfChincInv ============================================== Purpose ---------------- Computes the quantile or inverse of noncentral chi-squared cumulative distribution function. Format ---------------- .. function:: x = cdfChincInv(p, df, nonc) :param p: Probabilities at which to compute the inverse of noncentral chi-squared cumulative distribution function. :math:`0 < p < 1`. :type p: NxK matrix, Nx1 vector or scalar :param df: The degrees of freedom. :math:`df > 0`. :type df: ExE conformable with *p* :param nonc: The noncentrality parameter. Note: This is the square root of the noncentrality parameter that sometimes goes under the symbol :math:`\lambda`. :math:`nonc > 0`. :type nonc: ExE conformable with *p* :return x: each value of *x* is the value such that the noncentral chi-squared cdf with *df* degrees of freedom and *nonc* noncentrality evaluated at *x* is equal to the corresponding value of *p*. :rtype x: NxK matrix, Nx1 vector or scalar Examples ---------------- :: // Probabilities p = { .05, .1, .25, .5, .75, 0.90, 0.95 }; // Degrees of freedom df = 4; // Non-centrality parameter nonc = 2; print cdfChincInv(p, df, nonc); The code above returns: :: 1.7650 2.5583 4.3564 7.1016 10.6736 14.6157 17.3093 Remarks ------- For invalid inputs, :func:`cdfChincinv` will return a scalar error code which, when its value is assessed by function :func:`scalerr`, corresponds to the invalid input. If the first input is out of range, :func:`scalerr` will return a 1; if the second is out of range, scalerr will return a 2; etc. .. seealso:: :func:`cdfChinc`, :func:`cdfChic`, :func:`cdfFnc`, :func:`cdfTnc`