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<div><span style="background-color: rgb(255, 255, 255); color: rgb(34, 34, 34); font-family: arial, sans-serif; font-size: 12.8px; widows: 1;">Hello,</span></div>
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I'm using CppAD with Eigen. Multiplication of a double with an Eigen-Vector like this:</div>
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---</div>
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<div>template<typename Type></div>
<div>using Vector = Eigen::Matrix<Type, Eigen::Dynamic, 1>;</div>
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<div>Vector< AD< AD<double> > > tmp;</div>
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<div>tmp = tmp + 0.5 * tmp;</div>
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gives the following error</div>
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<p><b> </b><b>error: </b><b>invalid operands to binary expression ('double' and 'Vector<AD<AD<double> > >' (aka 'Eigen::Matrix<CppAD::AD<<wbr>CppAD::AD<double> >, -1, 1, 0, -1, 1>'))</b></p>
<p> tmp = tmp + 0.5 * tmp;</p>
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The error goes away if I do</div>
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---</div>
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tmp = tmp + AD<double>(0.5) * tmp;</div>
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---</div>
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Is this the right way to do it?</div>
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Btw. an AD< AD<double> > can be multiplied by a double just fine. </div>
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Thomas</div>
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