http://www.k-wave.org/forum/topic/the-first-order-equation-system-and-the-wave-equation Support for the k-Wave MATLAB toolbox en-US Tue, 12 May 2026 23:09:15 +0000 http://bbpress.org/?v=1.0.2 q http://www.k-wave.org/forum/search.php http://www.k-wave.org/forum/topic/the-first-order-equation-system-and-the-wave-equation#post-8727 Sun, 12 Mar 2023 14:48:20 +0000 JwJJJJ 8727@http://www.k-wave.org/forum/ <p>Hi Ben,</p> <p>Thanks for the reply!</p> <p>I saw that post. It is not just a problem of the scaling factor. I first try to integral f(t) to get F(t), multiple F(t) by the scaling factor and assign it to source.p. Then solve the systems with k-Wave and obtain the solution u(t,x). But the true source term f(t) does not equal to the left hand side of the wave equation when substituting the numerical u(t,x) to the equation. So how should I do to fix it?</p> <p>Best regards,<br /> Jiwei </p> http://www.k-wave.org/forum/topic/the-first-order-equation-system-and-the-wave-equation#post-8717 Wed, 08 Mar 2023 14:05:04 +0000 bencox 8717@http://www.k-wave.org/forum/ <p>Hi Jiwei, </p> <p>Is the problem a scaling factor?</p> <p>There is some explanation of the reason for the choice of scaling factor in k-Wave in this post:<br /> <a href="http://www.k-wave.org/forum/topic/using-sourcep-to-specify-pressure-distribution#post-4181">Using source.p to specify pressure distribution</a>.</p> <p>Hope that helps.</p> <p>Best wishes<br /> Ben </p> http://www.k-wave.org/forum/topic/the-first-order-equation-system-and-the-wave-equation#post-8707 Fri, 24 Feb 2023 11:22:29 +0000 JwJJJJ 8707@http://www.k-wave.org/forum/ <p>Hi,</p> <p>Thanks for this wonderful toolbox!</p> <p>I am trying to solve the inhomogeneous wave equation with the source term $f(t)\delta(x-x_0)$ using the k-Wave toolbox, i.e. </p> <p>$$ (\partial_t^2-\laplace)u=f(t)\delta(x-x_0).$$</p> <p>However, the solution seems wrong when I set source.p=f(t). The manual says that $f(t)=2/(c_0 N dx) \partial_t source.p$, but it does not work when I change the source.p using the equality. How should I set the source.p to get the expected solution? Any suggestion is appreciated!</p> <p>Thanks,<br /> Jiwei </p>