Chebyshev Approximation Multivariable Functions With the Interpolation of the Value of the Function and its Partial Derivative
Abstract
A method for constructing the Chebyshev approximation of a discrete the multivariable functions with reproduction of its values and values of its partial derivatives at given points is proposed. The idea of the method is based on the construction of the limiting average degree approximation with the appropriate interpolation conditions. An iterative scheme based on the method of least squares with a variable weight function was used to construct the average-level approximation. The presented results of the approximation of the function of one variable confirm the fulfillment of the characteristic property of the Chebyshev approximation with the reproduction of the values of the function and the values of its derivatives at the given points.
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