MapThread Replace?

*To*: mathgroup at smc.vnet.net*Subject*: [mg56451] MapThread Replace?*From*: leigh pascoe <leigh at cephb.fr>*Date*: Tue, 26 Apr 2005 01:32:51 -0400 (EDT)*Sender*: owner-wri-mathgroup at wolfram.com

Dear Mathgroup, Thanks to your help I have a list of 2x2 symbolic matrices involving the variables (x,y) generated by substituting the constants (a,b,c,d,e,f,g) from a list of such constants In[10]:= m:={{-D[D[L,x],x],-D[D[L,x],y]},{-D[D[L,y],x],-D[D[L,y],y]}}//MatrixForm In[11]:= mats=N[m /. subs] I also have a list of (y,x} values corresponding to each matrix in the list. I would like to substitute each (x,y) pair in the corresponding matrix and invert the resulting matrix to produce a list of the 2x2 inverses of the original matrices. I can invert the matrices symbolically with In[16]:= Map[Inv[#]&,mats] but I can't seem to find the correct command/syntax to substitute the corresponding (x,y) pair, either before or after the inversion step. Any suggestions appreciated. Leigh