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Evaluating polynomial

Evaluating polynomials or power Series USING Array formulas... [Pg.96]

In the work of King, Dupuis, and Rys [15,16], the mabix elements of the Coulomb interaction term in Gaussian basis set were evaluated by solving the differential equations satisfied by these matrix elements. Thus, the Coulomb matrix elements are expressed in the form of the Rys polynomials. The potential problem of this method is that to obtain the mabix elements of the higher derivatives of Coulomb interactions, we need to solve more complicated differential equations numerically. Great effort has to be taken to ensure that the differential equation solver can solve such differential equations stably, and to... [Pg.409]

To make the pair potentials flexible but fast to evaluate we chose the U-y rik) = W f qik) as low degree polynomials in... [Pg.216]

Curve fitting to data is most successhil when the form of the equation used is based on a known theoretical relationship between the variables associated with the data points, eg, use of the Clausius-Clapeyron equation for vapor pressure. In the absence of known theoretical relationships, polynomials are one of the most usehil forms to describe a curve. Polynomials are easy to evaluate the coefficients are linear and the degree, ie, the highest power appearing in the equation, is a convenient measure of smoothness. Lower orders yield smoother fits. [Pg.245]

Elimination of Ci and C3 from these equations will result in the desired relation between inlet Cj and outlet Co concentrations, although not in an exphcit form except for zero or first-order reactions. Alternatively, the Laplace transform could be found, inverted and used to evaluate segregated or max mixed conversions that are defined later. Inversion of a transform hke that of Fig. 23-8 is facilitated after replacing the exponential by some ratio of polynomials, a Pade approximation, as explained in books on hnear control theory. Numerical inversion is always possible. [Pg.2075]

It is now necessary to identify the correct functions of the capacity factor (k") to be used in equation (12) to evaluate the diffusivity. Knox [7] suggested the following approach which required a polynomial curve fitting procedure to identify the necessary constants. Rearranging equation (12),... [Pg.346]

R. NarayanaswamI and Howard M. Adelman, Evaluation of the Tensor Polynomial and Hoffman Strength Theories for Composite Materiais, Journal of Composite Materials, October 1977, pp. 366-377. [Pg.120]

R. C. Tennyson, D. MacDonald, arrd A. P. Nanyaro, Evaluation of the Tensor Polynomial Failure Criterion for Composite Materials, Journal of Composite Materials, January 1978, pp. 63-75. [Pg.120]

Evaluate the arithmetic mean of the 24 products assigned to the 24 rotations. I will call the resulting polynomial in the four symbols /p... [Pg.2]

The mass transfer, KL-a for a continuous stirred tank bioreactor can be correlated by power input per unit volume, bubble size, which reflects the interfacial area and superficial gas velocity.3 6 The general form of the correlations for evaluating KL-a is defined as a polynomial equation given by (3.6.1). [Pg.45]

G is then a generating function for these integrals, which occur as coefficients in its expansion in powers of u and and it can he evaluated with the use of the generating function for the associated Laguerre polynomials, given in equation (19). Thus we have... [Pg.727]

The next step is to evaluate the quantity Vn A) of interest in terms of 7j and 7,2, making it possible to extract those parameters Tj, T2,. ., , r, for which the minimal value of = P (A) is attained. The preceding polynomial... [Pg.660]

The recurrence relation (E.4) is useful for evaluating Pi(p) when the two preceding polynomials are known. [Pg.302]

Various compilations of densities for organic compounds have been published. The early Landolt-Bomstein compilation [23-ano] contained recommended values at specific temperatures. International Critical Tables [28-ano-l] provided recommended densities at 0 °C and values of constants for either a second or third order polynomial equation to represent densities as a function of temperature. This compilation also gave the range of validity of the equation and the limits of uncertainty, references used in the evaluation and those not considered. This compilation is one of the most comprehensive ever published. Timmermans [50-tim, 65-tim], Dreisbach [55-die, 59-die, 61-dre] and Landolt-Bomstein [71-ano] published additional compilations, primarily of experimental data. These compilations contained experimental data along with reference sources but no estimates of uncertainty for the data nor recommended values. [Pg.4]

The fraction undissolved data until the critical time can be least-square fitted to a third degree polynomial in time as dictated by Eq. (29). The moments of distribution ij, p2, and p3 can be evaluated from Eqs. (30) through (32), with three equations used to solve for three unknowns. These values may be used as first estimates in a nonlinear least-squares fit program, and the curve will, hence, reveal the best values of both shape factor, size distribution, and A -value. [Pg.183]

To evaluate the matrix polynomial in Eq. (9-23), we use the MATLAB function polyvalm () which applies the coefficients in p2 to the matrix A. [Pg.179]

The matrix elements of x4 can be evaluated with the use of the relation developed in Section 5.5.1 for the Hermite polynomials (See Appendix IX). In the notation employed here Eq. (5-99) becomes... [Pg.153]

An alternative definition involves the use of a generating function. This method is especially convenient for the evaluation of certain integrals of the Hermite polynomials and can be applied to other polynomials as well. For the Hermite polynomials the generating function can be written as... [Pg.268]

With its substitution in Eq. (99) it becomes evident from the orthogonality of the Hermite polynomials, that all matrix elements are equal to zero, with the exception of v = v — 1 and vf = u +1. Thus, the selection rule for vibrational transitions (in the harmonic approximation) is An — 1. It is not necessary to evaluate the matrix elements unless there is an interest in calculating the intensities of spectral features resulting from vibrational transitions (see problem 18). It should be evident that transitions such as Av - 3 are forbidden under this more restrictive selection rule, although they are permitted under the symmetry selection rule developed in the previous paragraphs. [Pg.369]

The evaluation of Pj.x) at a point other than at the defining points can be made with Neville s algorithm [Press et al. (1986)]. Let be the value at x of the unique function passing through the point (xi, y 1) or Pi = yi. Let P 2 be the value at x of the unique polynomial passing through the points Xi and x2. Likewise, Plfi, is the unique polynomial... [Pg.46]


See other pages where Evaluating polynomial is mentioned: [Pg.361]    [Pg.97]    [Pg.452]    [Pg.452]    [Pg.361]    [Pg.97]    [Pg.452]    [Pg.452]    [Pg.983]    [Pg.2335]    [Pg.216]    [Pg.477]    [Pg.478]    [Pg.49]    [Pg.269]    [Pg.31]    [Pg.77]    [Pg.97]    [Pg.145]    [Pg.97]    [Pg.121]    [Pg.29]    [Pg.242]    [Pg.116]    [Pg.4]    [Pg.616]    [Pg.61]    [Pg.160]    [Pg.92]    [Pg.161]    [Pg.164]   
See also in sourсe #XX -- [ Pg.96 ]




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