Re: ways to save the output from a notebook
- To: mathgroup at smc.vnet.net
- Subject: [mg93431] Re: [mg93408] ways to save the output from a notebook
- From: Bob Hanlon <hanlonr at cox.net>
- Date: Fri, 7 Nov 2008 06:02:37 -0500 (EST)
- Reply-to: hanlonr at cox.net
Immediate evaluation:
Clear[F];
F[x1_, x2_] = Module[{Yeni, Eski}, Yeni = x1^2;
Eski = x2^3]
x2^3
?F
Global`F
F[x1_,x2_]=x2^3
Table[F[x1, x2], {x1, 3}, {x2, 3}];
?F
Global`F
F[x1_,x2_]=x2^3
The definition of F has not been changed by use.
Delayed evaluation :
Clear[F];
F[x1_, x2_] := Module[{Yeni, Eski}, Yeni = x1^2;
Eski = x2^3]
?F
Global`F
F[x1_,x2_]:=Module[{Yeni,Eski},Yeni=x1^2;Eski=x2^3]
Table[F[x1, x2], {x1, 3}, {x2, 3}];
?F
Global`F
F[x1_,x2_]:=Module[{Yeni,Eski},Yeni=x1^2;Eski=x2^3]
Again, the definition of F has not been changed by use.
Delayed evaluation with embedded immediate evaluation:
Clear[F];
F[x1_, x2_] := F[x1, x2] = Module[{Yeni, Eski}, Yeni = x1^2;
Eski = x2^3];
Note that the patterns only appear on the far LHS
?F
Global`F
F[x1_,x2_]:=F[x1,x2]=Module[{Yeni,Eski},Yeni=x1^2;Eski=x2^3]
Table[F[x1, x2], {x1, 3}, {x2, 3}];
?F
Global`F
F[1,1]=1
F[1,2]=8
F[1,3]=27
F[2,1]=1
F[2,2]=8
F[2,3]=27
F[3,1]=1
F[3,2]=8
F[3,3]=27
F[x1_,x2_]:=F[x1,x2]=Module[{Yeni,Eski},Yeni=x1^2;Eski=x2^3]
The definition of F remembers the results of each call. This is particularly useful to speed up multiple calls to recursive defintions. See
http://reference.wolfram.com/mathematica/tutorial/FunctionsThatRememberValuesTheyHaveFound.html
Bob Hanlon
---- Tugrul Temel <temelt at xs4all.nl> wrote:
=============
Dear All,
Suppose that I have:
F[x1_,x2_]:=F[x1_,x2_]=
Module[
{Yeni, Eski},
Yeni=x1^2 ;
Eski=x2^3
]
What role does F[x1_,x2_]:=F[x1_,x2_] have? What does it do?
Regards,
Tugrul