Better Set or Set Delayed ?
- To: mathgroup at smc.vnet.net
- Subject: [mg45138] Better Set or Set Delayed ?
- From: "Jean.Pellegri" <Jean.Pellegri at wanadoo.fr>
- Date: Thu, 18 Dec 2003 06:55:14 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
phi is the function : phi[u_,v_]=u^4+v^3
For calculating the Laplacian at u=3 and v=4 ,
is better :
this ??
Laplacien2[f_][x_,y_]:=
Module[{expr,p,q,Dpp,Dqq,subs},
expr = f[p,q]; (* Set *)
Dpp=D[expr,{p,2}];
Dqq=D[expr,{q,2}];
subs={p->x,q->y};
Dpp+Dqq/.subs]
Laplacien2[phi][3,4]
or this ???
Laplacien3[f_][x_,y_]:=
Module[{g,p,q,Dpp,Dqq,subs},
g[p_,q_] = f[p,q]; (* Set *)
Dpp=D[g[p,q],{p,2}];
Dqq=D[g[p,q],{q,2}];
subs={p->x,q->y};
Dpp+Dqq/.subs]
Laplacien3[phi][3,4]
or this ????
Laplacien4[f_][x_,y_]:=
Module[{g,p,q,Dpp,Dqq,subs},
g[p_,q_] := f[p,q]; (* Set Delayed *)
Dpp=D[g[p,q],{p,2}];
Dqq=D[g[p,q],{q,2}];
subs={p->x,q->y};
Dpp+Dqq/.subs]
Laplacien4[phi][3,4]
Thanks and Ciao
--
< Jean Pellegri >
"fortitudo mea in rota"
93100 Montreuil