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Re: changing variables in differential equations

• To: mathgroup at smc.vnet.net
• Subject: [mg100650] Re: changing variables in differential equations
• From: dh <dh at metrohm.com>
• Date: Wed, 10 Jun 2009 05:34:44 -0400 (EDT)
• References: <h0l48t$opp$1@smc.vnet.net>

Hi Andre,

you start out with one independent variable x. Then after the variable 

transformation you have 2 (u,v)! Therefore, this can not be a regular 

transformation.

Daniel



Andre Hautot wrote:

> Hello,

> Given an ordinary differential equation of order n, H(x,y,y',y'',...)=0

> Given the change of variables : x=x(u,v) and y=y(u,v)

> How to calculate (hopefully recursively) y', y'', and so on as functions 

> of say : u, v', v''

> 

> In other words how to translate automatically the differential equation 

> in terms of the new variables ?

> Thanks in advance