Re: operate a matrix of derivations

*To*: mathgroup at smc.vnet.net*Subject*: [mg39470] Re: operate a matrix of derivations*From*: Paul Abbott <paul at physics.uwa.edu.au>*Date*: Mon, 17 Feb 2003 18:17:10 -0500 (EST)*Organization*: The University of Western Australia*References*: <b1l15i$i8o$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

In article <b1l15i$i8o$1 at smc.vnet.net>, iselig at techunix.technion.ac.il (ilan) wrote: > I want to make a matrix of derivations, so I will be able to multiply > it by a matrix of functions and get the result matrix > simple example: > > |d/dx 0 | |xy x| |y 1| > | |.| |=| | > |d/dy d/dx| |x+y 3| |x+1 0| > > thank you Here is one way. Matrix of operators: operator = {{D[#, x]& , 0 # & }, {D[#, y]& , D[#, x]& }} Matrix of functions: functions = {{x y, x}, {x + y, 3}} Compose them: Inner[Compose, operator, functions] Cheers, Paul -- Paul Abbott Phone: +61 8 9380 2734 School of Physics, M013 Fax: +61 8 9380 1014 The University of Western Australia (CRICOS Provider No 00126G) 35 Stirling Highway Crawley WA 6009 mailto:paul at physics.uwa.edu.au AUSTRALIA http://physics.uwa.edu.au/~paul