ndsolve ndsv problem
- To: mathgroup at smc.vnet.net
- Subject: [mg79829] ndsolve ndsv problem
- From: "Chris Chiasson" <chris at chiasson.name>
- Date: Mon, 6 Aug 2007 03:35:03 -0400 (EDT)
Steps to reproduce: 1. Issue this command (given to you in InputFrom due to a copy/paste problem) NDSolve[0.0005635632304299039*psi[R] == (2*Derivative[1][psi][R])/R + Derivative[2][psi][R] && Derivative[1][psi][1] == 7.017487714753473 && psi[Infinity] == 0, psi, R] 2. Notice the warning (input returns unevaluated): NDSolve::ndsv: Cannot find starting value for the variable psi^\[Prime]. >> 3. The documentation for this error says: Generated when NDSolve is unable to solve the initial conditions to find a starting value in an initial value problem. This message can be generated by a variety of errors in the specification of initial conditions. Expected result: Something more helpful Maybe I am being too hard on Mathematica here, but maybe not, considering what Rob Knapp said in 1999 about Mathematica 4: http://forums.wolfram.com/mathgroup/archive/2000/Jun/msg00070.html Also, it appears the documentation hasn't changed for this error: http://forums.wolfram.com/mathgroup/archive/2000/Jun/msg00068.html -- http://chris.chiasson.name/