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Subject: avoiding loops to built a z matrix of the most efficient form From: Jose Date: 25 Mar, 2009 15:40:19 Message: 1 of 36 
Hello us, and everyone. 
Subject: avoiding loops to built a z matrix of the most efficient form From: Matt Fig Date: 25 Mar, 2009 16:24:01 Message: 2 of 36 
Loops have not been slow in Matlab for several releases now. OFTEN, running a loop is going to be faster than vectorizing the code. Not always, but it should definitely not be a surprise to find this is the case in any given situation. 
Subject: avoiding loops to built a z matrix of the most efficient form From: Roger Stafford Date: 25 Mar, 2009 16:34:01 Message: 3 of 36 
"Jose " <jose.l.vega@gmail.com> wrote in message <gqdj93$qa4$1@fred.mathworks.com>... 
Subject: avoiding loops to built a z matrix of the most efficient form From: Bruno Luong Date: 25 Mar, 2009 16:44:02 Message: 4 of 36 
"Jose " <jose.l.vega@gmail.com> wrote in message <gqdj93$qa4$1@fred.mathworks.com>... 
Subject: avoiding loops to built a z matrix of the most efficient form From: Jose Date: 25 Mar, 2009 17:52:01 Message: 5 of 36 
"Bruno Luong" <b.luong@fogale.findmycountry> wrote in message <gqdn0i$a5r$1@fred.mathworks.com>... 
Subject: avoiding loops to built a z matrix of the most efficient form From: Roger Stafford Date: 25 Mar, 2009 18:18:01 Message: 6 of 36 
"Jose " <jose.l.vega@gmail.com> wrote in message <gqdr01$jp4$1@fred.mathworks.com>... 
Subject: avoiding loops to built a z matrix of the most efficient form From: Jose Date: 25 Mar, 2009 18:43:01 Message: 7 of 36 
"Roger Stafford" <ellieandrogerxyzzy@mindspring.com.invalid> wrote in message <gqdsgp$aic$1@fred.mathworks.com>... 
Subject: avoiding loops to built a z matrix of the most efficient form From: Bruno Luong Date: 25 Mar, 2009 18:49:01 Message: 8 of 36 
"Jose " <jose.l.vega@gmail.com> wrote in message <gqdr01$jp4$1@fred.mathworks.com>... 
Subject: avoiding loops to built a z matrix of the most efficient form From: Bruno Luong Date: 25 Mar, 2009 18:55:03 Message: 9 of 36 
"Jose " <jose.l.vega@gmail.com> wrote in message <gqdtvl$n5j$1@fred.mathworks.com>... 
Subject: avoiding loops to built a z matrix of the most efficient form From: Jose Date: 25 Mar, 2009 19:09:01 Message: 10 of 36 
"Bruno Luong" <b.luong@fogale.findmycountry> wrote in message <gqduat$hug$1@fred.mathworks.com>... 
Subject: avoiding loops to built a z matrix of the most efficient form From: Bruno Luong Date: 25 Mar, 2009 19:47:01 Message: 11 of 36 
Yet another way: 
Subject: avoiding loops to built a z matrix of the most efficient form From: Jose Date: 25 Mar, 2009 20:34:01 Message: 12 of 36 
"Bruno Luong" <b.luong@fogale.findmycountry> wrote in message <gqe1nl$cra$1@fred.mathworks.com>... 
Subject: avoiding loops to built a z matrix of the most efficient form From: Bruno Luong Date: 25 Mar, 2009 21:02:02 Message: 13 of 36 
And what about this? 
Subject: avoiding loops to built a z matrix of the most efficient form From: Matt Fig Date: 25 Mar, 2009 21:10:02 Message: 14 of 36 
Just to show that the old For loop isn't as uncompetitive as it seems, try this out for giggles: 
Subject: avoiding loops to built a z matrix of the most efficient form From: Matt Fig Date: 25 Mar, 2009 21:27:01 Message: 15 of 36 
As is often the case, I noticed an improvement that could be made after I posted. On my machine this is as fast as any other. Though definitely not as cool as Bruno's final offer. 
Subject: avoiding loops to built a z matrix of the most efficient form From: Matt Fig Date: 25 Mar, 2009 21:33:01 Message: 16 of 36 
"Matt Fig" <spamanon@yahoo.com> wrote in message <gqe7j5$evd$1@fred.mathworks.com>... 
Subject: avoiding loops to built a z matrix of the most efficient form From: Jose Date: 26 Mar, 2009 00:09:01 Message: 17 of 36 
"Matt Fig" <spamanon@yahoo.com> wrote in message <gqe7ud$9vm$1@fred.mathworks.com>... 
Subject: avoiding loops to built a z matrix of the most efficient form From: Matt Fig Date: 26 Mar, 2009 00:13:01 Message: 18 of 36 

Subject: avoiding loops to built a z matrix of the most efficient form From: Matt Fig Date: 26 Mar, 2009 00:35:02 Message: 19 of 36 
Hats off to Bruno! I didn't see the shorter code he posted earlier. I don't think I can beat that one with a For loop. Nice ;) 
Subject: avoiding loops to built a z matrix of the most efficient form From: Jose Date: 26 Mar, 2009 00:49:01 Message: 20 of 36 
"Matt Fig" <spamanon@yahoo.com> wrote in message <gqehad$k7c$1@fred.mathworks.com>... 
Subject: avoiding loops to built a z matrix of the most efficient form From: us Date: 26 Mar, 2009 06:07:08 Message: 21 of 36 
"Jose" 
Subject: avoiding loops to built a z matrix of the most efficient form From: Bruno Luong Date: 26 Mar, 2009 06:48:04 Message: 22 of 36 
I must agree with us here. If there is one thing to be learn from the thread is: Do not describe only half of the problem; All aspects of the problem are their importance when optimizing. If some characteristics are hidden, no effective optimization could be achieved. 
Subject: avoiding loops to built a z matrix of the most efficient form From: Bruno Luong Date: 26 Mar, 2009 07:11:02 Message: 23 of 36 
"Jose " <jose.l.vega@gmail.com> wrote in message <gqeh2t$aqc$1@fred.mathworks.com>... 
Subject: avoiding loops to built a z matrix of the most efficient form From: Jose Date: 26 Mar, 2009 10:54:00 Message: 24 of 36 
"Bruno Luong" <b.luong@fogale.findmycountry> wrote in message <gqf9q6$gad$1@fred.mathworks.com>... 
Subject: avoiding loops to built a z matrix of the most efficient form From: Jose Date: 26 Mar, 2009 15:55:04 Message: 25 of 36 
"Bruno Luong" <b.luong@fogale.findmycountry> wrote in message <gqf9q6$gad$1@fred.mathworks.com>... 
Subject: avoiding loops to built a z matrix of the most efficient form From: Bruno Luong Date: 26 Mar, 2009 18:05:02 Message: 26 of 36 
"Jose " <jose.l.vega@gmail.com> wrote in message <gqg8go$o5j$1@fred.mathworks.com>... 
Subject: avoiding loops to built a z matrix of the most efficient form From: Jose Date: 26 Mar, 2009 18:30:20 Message: 27 of 36 
"Bruno Luong" <b.luong@fogale.findmycountry> wrote in message <gqgg4e$98j$1@fred.mathworks.com>... 
Subject: avoiding loops to built a z matrix of the most efficient form From: Matt Fig Date: 26 Mar, 2009 18:58:01 Message: 28 of 36 
Why is pm being calculated when it is not being used? Why are you preallocating zm but not the array that is actually growing in the loop (lpms)? 
Subject: avoiding loops to built a z matrix of the most efficient form From: Jose Date: 26 Mar, 2009 19:10:17 Message: 29 of 36 
"Matt Fig" <spamanon@yahoo.com> wrote in message <gqgj7p$dno$1@fred.mathworks.com>... 
Subject: avoiding loops to built a z matrix of the most efficient form From: Matt Fig Date: 26 Mar, 2009 19:21:02 Message: 30 of 36 
> I need pm 
Subject: avoiding loops to built a z matrix of the most efficient form From: Jose Date: 26 Mar, 2009 19:50:16 Message: 31 of 36 
"Matt Fig" <spamanon@yahoo.com> wrote in message <gqgkiu$il3$1@fred.mathworks.com>... 
Subject: avoiding loops to built a z matrix of the most efficient form From: Bruno Luong Date: 26 Mar, 2009 19:56:01 Message: 32 of 36 
"Jose " <jose.l.vega@gmail.com> wrote in message <gqgm9o$jif$1@fred.mathworks.com>... 
Subject: avoiding loops to built a z matrix of the most efficient form From: us Date: 26 Mar, 2009 20:08:01 Message: 33 of 36 
"Bruno Luong" 
Subject: avoiding loops to built a z matrix of the most efficient form From: Jose Date: 26 Mar, 2009 20:32:02 Message: 34 of 36 
"Bruno Luong" <b.luong@fogale.findmycountry> wrote in message <gqgmkh$cj5$1@fred.mathworks.com>... 
Subject: avoiding loops to built a z matrix of the most efficient form From: Matt Fig Date: 27 Mar, 2009 04:19:01 Message: 35 of 36 
Well, you can shave off about 10% of the runtime by using the following: 
Subject: avoiding loops to built a z matrix of the most efficient form From: Jose Date: 27 Mar, 2009 12:17:57 Message: 36 of 36 
"Matt Fig" <spamanon@yahoo.com> wrote in message <gqhk3l$4eb$1@fred.mathworks.com>... 
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