High-order derivatives
Hello, I am trying to solve a wave equation by the PDE coefficient module, the variable is u. I want to look at the second time derivative of u, i.e., utt. But when I plot it, all I got is zero, which...
View ArticleRe: High-order derivatives
Hi for higher order derivatives have you checed out www.comsol.com/support/knowledgebase/816/ And do not forget that there is a few settings as "click" "objects" on the bottom left of the "solver...
View ArticleRe: High-order derivatives
You need to open the Solver Manager and go to the Output page. There, check "Include time derivatives". Solve the problem again. Then you should be able to plot utt. Niklas
View ArticleRe: High-order derivatives
thanks for your reply Is there a way to also look at the third order derivative? I tried diff(utt,t), and got zero, diff(diff(diff(u,t),t),t) did not work either But diff(diff(diff(u^2,t),t),t) did...
View ArticleRe: High-order derivatives
thanks for your reply Is there a way to also look at the third order derivative? I tried diff(utt,t), and got zero, diff(diff(diff(u,t),t),t) did not work either But diff(diff(diff(u^2,t),t),t) did...
View ArticleRe: High-order derivatives
thanks for your reply Is there a way to also look at the third order derivative? I tried diff(utt,t), and got zero, diff(diff(diff(u,t),t),t) did not work either But diff(diff(diff(u^2,t),t),t) did...
View ArticleRe: High-order derivatives
Hi, The "diff" and "pdiff" operators changed name to "d" and "pd", respectively, starting from version 3.5a, so, for example, d(u,x) is now the correct syntax for du/dx. Magnus Ringh COMSOL
View ArticleHigh-order derivatives
Hello, I am trying to solve a wave equation by the PDE coefficient module, the variable is u. I want to look at the second time derivative of u, i.e., utt. But when I plot it, all I got is zero, which...
View ArticleRe: High-order derivatives
Hi for higher order derivatives have you checed out www.comsol.com/support/knowledgebase/816/ And do not forget that there is a few settings as "click" "objects" on the bottom left of the "solver...
View ArticleRe: High-order derivatives
You need to open the Solver Manager and go to the Output page. There, check "Include time derivatives". Solve the problem again. Then you should be able to plot utt. Niklas
View ArticleRe: High-order derivatives
thanks for your reply Is there a way to also look at the third order derivative? I tried diff(utt,t), and got zero, diff(diff(diff(u,t),t),t) did not work either But diff(diff(diff(u^2,t),t),t) did...
View ArticleRe: High-order derivatives
thanks for your reply Is there a way to also look at the third order derivative? I tried diff(utt,t), and got zero, diff(diff(diff(u,t),t),t) did not work either But diff(diff(diff(u^2,t),t),t) did...
View ArticleRe: High-order derivatives
thanks for your reply Is there a way to also look at the third order derivative? I tried diff(utt,t), and got zero, diff(diff(diff(u,t),t),t) did not work either But diff(diff(diff(u^2,t),t),t) did...
View ArticleRe: High-order derivatives
Hi, The "diff" and "pdiff" operators changed name to "d" and "pd", respectively, starting from version 3.5a, so, for example, d(u,x) is now the correct syntax for du/dx. Magnus Ringh COMSOL
View ArticleHigh-order derivatives
Hello, I am trying to solve a wave equation by the PDE coefficient module, the variable is u. I want to look at the second time derivative of u, i.e., utt. But when I plot it, all I got is zero, which...
View ArticleRe: High-order derivatives
Hi for higher order derivatives have you checed out www.comsol.com/support/knowledgebase/816/ And do not forget that there is a few settings as "click" "objects" on the bottom left of the "solver...
View ArticleRe: High-order derivatives
You need to open the Solver Manager and go to the Output page. There, check "Include time derivatives". Solve the problem again. Then you should be able to plot utt. Niklas
View ArticleRe: High-order derivatives
thanks for your reply Is there a way to also look at the third order derivative? I tried diff(utt,t), and got zero, diff(diff(diff(u,t),t),t) did not work either But diff(diff(diff(u^2,t),t),t) did...
View Article
