Recent content by hitmre

Thank you fzero! It seems a good idea. I am wondering whether this definition $$ C[f_1,f_2] = \frac{ d_Y ( \hat{D}[f_1], \hat{D}[f_2] )}{d_X (f_1,f_2)} $$ is widely use. Many thanks! joseph

Hi all, I understand some PDE is linear like \frac{\partial f}{\partial t}+\frac{\partial f}{\partial x}=0 while some PDE is nonlinear like \frac{\partial f}{\partial t}+f\frac{\partial f}{\partial x}=0 Some PDE is weak nonlinear and some is strong nonlinear. I am wondering whether...