Emil Shoukralla

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We provide Interpolant solutions to the Apple integral equations that emerge in climate, ‎‎atmosphere, heat transfer, superfluid, astrophysics, solid mechanics, scattering theory, ‎‎spectroscopy, stereology, elasticity theory, and plasma physics, and other fields. We ‎developed ‎adequate formulas for the optimal distribution of kernel nodes to address the ‎kernel’s ‎singularity, ensuring that the kernel does not reach infinity when one of the two ‎variables ‎approaches the other. Four matrices represent the data function, whereas five ‎matrices ‎represent the kernel. We achieved two formulas for the matrix-vector single ‎interpolated ‎solution, the first based on interpolated the data function while the second based ‎on ‎interpolated the kernel only. The matrix-vector single interpolated solution has two ‎formulas: ‎the first is based on interpolating the data function and the kernel, while the second ‎is based ‎on interpolating only the kernel. The first formula simply involves the calculation of ‎two ‎matrices: the elements of the first matrix are correspond to the functional values of the ‎data ‎function, and the elements of the second matrix correspond to the functional values of ‎the ‎kernel at the two sets of nodes that are associated with the kernel’s variables. When ‎compared ‎to the solutions provided by other approaches, the lower-degree interpolated ‎solutions to three ‎cases were found to be convergent to the exact solutions with a minimum ‎CPU time and high ‎accuracy, demonstrating the novelty and simplicity of the proposed ‎method as well as the ‎accuracy of the results.‎
There are many scientific problems related to the topic of interpolation, especially for non-‎continuous functions, as well as the evaluating of the integrals of such non-continuous ‎‎functions. These needs appear clearly in the development of profit and loss plans in economic ‎‎projects, stock exchange transactions, and investment funds, solving ecological issues and ‎‎recording data on the evolution of epidemics and virology. We investigate a new straightforward ‎‎method for interpolating and integrating discontinuous valued functions. The method is based ‎‎on some modified ‎matrix-vector ‎barycentric Lagrange interpolation formulas. We developed ‎‎seven rules for the ‎optimum distribution of nodes ‎inside the domain of integration; five for ‎‎single-valued ‎discontinuous functions, and two rules for the two independent variables ‎‎discontinuous ‎functions. We designed these rules to be depending on the length of the ‎‎integration domain and ‎the degree of the interpolant polynomials. Thus, we obtained uniform ‎‎interpolation and the ‎minimum roundoff errors. Based on these rules with the application of the ‎‎modified matrix-vector barycentric formulas, we easily isolated the singularities of the ‎‎interpolant integrands and ‎evaluated the corresponding interpolant integral values with super ‎‎accuracy. The numerical ‎solutions of the given five examples show the ‎super accuracy, and ‎‎efficiency of the ‎presented method compared with a cited method.‎ ‎ Keywords- interpolation, singular integrals, computational methods‎