DEtools[integrate_sols] - integrate the solutions of a differential operator or equation
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Calling Sequence
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integrate_sols(L, domain)
integrate_sols(eqn, dvar)
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Parameters
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L
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differential operator
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domain
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list containing two names
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eqn
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homogeneous linear differential equation
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dvar
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dependent variable
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Description
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The input L is a differential operator. This procedure computes an operator M of minimal order such that any solution of L has an antiderivative which is a solution of M.
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If the argument domain is omitted then the differential specified by the environment variable _Envdiffopdomain is used. If this environment variable is not set then the argument domain may not be omitted.
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Instead of a differential operator, the input can also be a linear homogeneous differential equation having rational function coefficients. In this case the second argument must be the dependent variable.
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This function is part of the DEtools package, and so it can be used in the form integrate_sols(..) only after executing the command with(DEtools). However, it can always be accessed through the long form of the command by using DEtools[integrate_sols](..).
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Examples
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The result was only the operator M. For an example where both M and r are obtained, consider:
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Regarding the meaning of the second element in the output of integrate_sols, consider the following second order ODE and its solution.
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The ODE satisfied by the integral of sol is given by the first element of the output of integrate_sols while the formula for computing its solution (as a function of sol) is given by the second element.
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So the solution to ode2 is obtained by substituting sol into integral_of_sol.
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That sol2 is the integral of sol can also be verified as follows: Differentiate sol2 and verify that it is equal to sol.
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References
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Abramov, S.A., and van Hoeij, M. "A method for the Integration of Solutions of Ore Equations." ISSAC '97 Proceedings, pp. 172-175. 1997.
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