Ore_algebra[Ore_to_diff] - convert a differential operator to a differential equation
Ore_algebra[Ore_to_shift] - convert a shift operator to a recurrence equation
Ore_algebra[Ore_to_DESol] - convert a differential operator to a DESol structure
Ore_algebra[Ore_to_RESol] - convert a shift operator to an RESol structure
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Calling Sequence
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Ore_to_diff(G, f, A)
Ore_to_diff(G, f, A, 'D')
Ore_to_shift(G, u, A)
Ore_to_shift(G, u, A, 'indexed')
Ore_to_DESol(P, f, A)
Ore_to_RESol(P, u, A)
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Parameters
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G
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list of operators of the Ore algebra A
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P
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operator of the Ore algebra A
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f
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expression denoting a mathematical function
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A
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Ore algebra table
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Description
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The Ore_to_diff command converts a differential operator or a list of differential operators of the skew algebra A into a differential equation or a list of differential equations in the function f. The output is expressed in terms of the diff function by default, or in terms of the D function when the optional parameter is set.
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The Ore_to_DESol command converts a single differential operator of the skew algebra A into a DESol structure in the function f.
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The Ore_to_shift command converts a shift operator or a list of shift operators of the skew algebra A into a recurrence equation or a list of recurrence equations in the sequence u. The output is expressed in functional notation ( ) by default, or in the indexed notation ( ) when the optional argument is set.
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The Ore_to_RESol command converts a single recurrence operator of the skew algebra A into an RESol structure in the sequence u.
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Examples
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Differential case.
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Euler case.
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Recurrence case.
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Multivariate differential case.
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These are operators for BesselJ(mu,x*y^2).
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No conversion is available to a multivariate DESol.
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