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[mathcad] resizing a matrix/vector
Author: Tom Boni    Posted: Fri, 5 Sep 2008 12:10:31 -0700 (
What options are there for resizing a matrix/vector? For instance lets say I have a 1 x 9 vector and want to make it 1 x 6 or 1 x 12? Right now, I just create a new (empty) vector of the desired size... Just thought I'd ask in case there is an "on-the-fly" method that I am not aware of... In many cases the elements of the new vector are the same as elements in the existing vector... --- The Mathcad List - Discussion, Support & News Contributions: /> Hosted by: Adept Scientific http://www.adeptscience.com List Archive: http://lists.adeptscience.co.uk/ --- Would you like this to come to a different email address? --- Simply leave the mailing list (see below) and re-join by sending a blank email from the new address to: or --- You are currently subscribed to mathcad as: /> To unsubscribe send a blank email to />

RE: [mathcad] resizing a matrix/vector
Author: Philip Oakley    Posted: Sat, 6 Sep 2008 12:36:01 +0100
Tom, The hidden feature of MathCAD is that in reality it doesn't have any variables. It has named constants that exist for a part of a page between the point it is defined and the point that another of the same name is defined. The only 'unless' is that within a programme (with the black bar and the left pointing arrows) those variables are true variables that can be overwritten and are thrown away at the end of the execution. So if you define v:=stack(1,2,3,4,5,6,7,8,9) then v:submatrix(v,2,7,0,0) you now have two variables 'v' (both vectors) on the page and if you type "v=" and then drag it around, you will see the two results depending on where the "v=" is on the page. Also, if you have a set of indices 'index' to be used to pull out and re-order it you can use. you can even convert it to a little programme if needed. i:=0;..last(index) v[i]:=v[(index[i])] will also do it (I have closed the [] brackets subscripts, shown :=, and the range ;.. Hope that helps. Philip -----Original Message----- From: Tom Boni /> Sent: 05 September 2008 8:11 PM To: /> Subject: [mathcad] resizing a matrix/vector What options are there for resizing a matrix/vector? For instance lets say I have a 1 x 9 vector and want to make it 1 x 6 or 1 x 12? Right now, I just create a new (empty) vector of the desired size... Just thought I'd ask in case there is an "on-the-fly" method that I am not aware of... In many cases the elements of the new vector are the same as elements in the existing vector... --- The Mathcad List - Discussion, Support & News Contributions: /> Hosted by: Adept Scientific http://www.adeptscience.com List Archive: http://lists.adeptscience.co.uk/ --- Would you like this to come to a different email address? --- Simply leave the mailing list (see below) and re-join by sending a blank email from the new address to: or --- You are currently subscribed to mathcad as: /> To unsubscribe send a blank email to /> --- The Mathcad List - Discussion, Support & News Contributions: /> Hosted by: Adept Scientific http://www.adeptscience.com List Archive: http://lists.adeptscience.co.uk/ --- Would you like this to come to a different email address? --- Simply leave the mailing list (see below) and re-join by sending a blank email from the new address to: or --- You are currently subscribed to mathcad as: /> To unsubscribe send a blank email to
Attachments:  reorder a vector.mcd  reorder a vector.xmcdz

Re: [mathcad] resizing a matrix/vector
Author: Radovan Omorjan    Posted: Sat, 06 Sep 2008 21:22:12 -0700
Look at the attached file (Mcad v.11) For manipulating matrices you can use submatrix - extracting a submatrix from a matrix append - joining matrices horizontally (must have the same number of rows) stack - joining matrices vertically (must have the same number of columns) > What options are there for resizing a matrix/vector? > > For instance lets say I have a 1 x 9 vector and want to make it 1 x 6 or 1 x 12? > > Right now, I just create a new (empty) vector of the desired size... > > Just thought I'd ask in case there is an "on-the-fly" method that I am not aware of... > > In many cases the elements of the new vector are the same as elements in the existing vector... --- The Mathcad List - Discussion, Support & News Contributions: /> Hosted by: Adept Scientific http://www.adeptscience.com List Archive: http://lists.adeptscience.co.uk/ --- Would you like this to come to a different email address? --- Simply leave the mailing list (see below) and re-join by sending a blank email from the new address to: or --- You are currently subscribed to mathcad as: /> To unsubscribe send a blank email to
Attachments:  rowmatrix.mcd

Re: [mathcad] resizing a matrix/vector
Author: =?ISO-8859-1?Q?Steen_Gro=F0e?=    Posted: Sat, 06 Sep 2008 13:33:11 +0200
> What options are there for resizing a matrix/vector? > > For instance lets say I have a 1 x 9 vector and want to make it 1 x > 6 or 1 x 12? > > Right now, I just create a new (empty) vector of the desired > size... > > Just thought I'd ask in case there is an "on-the-fly" method that I > am not aware of... > > In many cases the elements of the new vector are the same as > elements in the existing vector... Sizing up is just adding the new elements. Sizing down is slightly more difficult. You can use submatrix for that. Med venlig hilsen :-) Steen Groðe http://www.grode.dk --- The Mathcad List - Discussion, Support & News Contributions: /> Hosted by: Adept Scientific http://www.adeptscience.com List Archive: http://lists.adeptscience.co.uk/ --- Would you like this to come to a different email address? --- Simply leave the mailing list (see below) and re-join by sending a blank email from the new address to: or --- You are currently subscribed to mathcad as: /> To unsubscribe send a blank email to />

Re: [mathcad] resizing a matrix/vector
Author: David G Shaw    Posted: Sun, 07 Sep 2008 00:04:58 +0000
Hi Tom, I have used the functions stack() and augment() from time to time. stack(,,,,) adds elements, vectors or matrices to the vertical structure of a vector or matrix. I use stack often to expand an arbitrary vector to get nice round numbers (2^N) for FFTs. augment(,,,,) adds columns together to widen a matrix or lengthen a transposed vector. Don't know the equivalent for reducing matrices. You can always delete rows or columns though. Help shows: " Deleting RowsThis procedure deletes the row containing the selected element together with an appropriate number of rows below it. " Hope these might help. Regards, David Shaw -------------- Original message from Tom Boni -------------- > What options are there for resizing a matrix/vector? > > For instance lets say I have a 1 x 9 vector and want to make it 1 x 6 or 1 x 12? > > Right now, I just create a new (empty) vector of the desired size... > Just thought I'd ask in case there is an "on-the-fly" method that I am not aware > of... > In many cases the elements of the new vector are the same as elements in the > existing vector... > > > > > --- > The Mathcad List - Discussion, Support & News > Contributions: /> > Hosted by: Adept Scientific http://www.adeptscience.com > List Archive: http://lists.adeptscience.co.uk/ > --- > Would you like this to come to a different email address? > --- > Simply leave the mailing list (see below) and re-join by > sending a blank email from the new address to: > or > --- > You are currently subscribed to mathcad as: unsubscribe send a blank email to > /> --- The Mathcad List - Discussion, Support & News Contributions: /> Hosted by: Adept Scientific http://www.adeptscience.com List Archive: http://lists.adeptscience.co.uk/ --- Would you like this to come to a different email address? --- Simply leave the mailing list (see below) and re-join by sending a blank email from the new address to: or --- You are currently subscribed to mathcad as: /> To unsubscribe send a blank email to

Re: [mathcad] resizing a matrix/vector
Author: Radovan Omorjan    Posted: Sat, 06 Sep 2008 21:27:22 -0700
Forgot to attach the file, sorry > What options are there for resizing a matrix/vector? > > For instance lets say I have a 1 x 9 vector and want to make it 1 x 6 or 1 x 12? > > Right now, I just create a new (empty) vector of the desired size... > > Just thought I'd ask in case there is an "on-the-fly" method that I am not aware of... > > In many cases the elements of the new vector are the same as elements in the existing vector... --- The Mathcad List - Discussion, Support & News Contributions: /> Hosted by: Adept Scientific http://www.adeptscience.com List Archive: http://lists.adeptscience.co.uk/ --- Would you like this to come to a different email address? --- Simply leave the mailing list (see below) and re-join by sending a blank email from the new address to: or --- You are currently subscribed to mathcad as: /> To unsubscribe send a blank email to
Attachments:  rowmatrix.mcd

RE: [mathcad] resizing a matrix/vector
Author: Stuart Bruff    Posted: Sat, 6 Sep 2008 15:51:56 +0100
Tom, If you want to expand an array, simply set the values you want for the new elements. A standard way of creating a vector is to set the largest index to 0, which returns a vector of all zeros; for many applications this improves execution speed as Mathcad only has to create the array once, rather than having to keep bolting new elements on (which can be time-consuming, particularly for large arrays). To shrink an array, use the submatrix function, eg if v is your 9-element vector, then submatrix(v,0,5,0,0) will return a 6-element vector comprising the first six elements of v Stuart Calling convention: submatrix(vector,first_row,last_row,first_col,last_col) -----Original Message----- From: Tom Boni Sent: 05 September 2008 8:11 PM To: /> Subject: [mathcad] resizing a matrix/vector What options are there for resizing a matrix/vector? For instance lets say I have a 1 x 9 vector and want to make it 1 x 6 or 1 x 12? Right now, I just create a new (empty) vector of the desired size... Just thought I'd ask in case there is an "on-the-fly" method that I am not aware of... In many cases the elements of the new vector are the same as elements in the existing vector... --- The Mathcad List - Discussion, Support & News Contributions: /> Hosted by: Adept Scientific http://www.adeptscience.com List Archive: http://lists.adeptscience.co.uk/ --- Would you like this to come to a different email address? --- Simply leave the mailing list (see below) and re-join by sending a blank email from the new address to: or --- You are currently subscribed to mathcad as: To unsubscribe send a blank email to /> -- This message has been scanned for viruses and dangerous content by Houxou, and is believed to be clean. --- The Mathcad List - Discussion, Support & News Contributions: /> Hosted by: Adept Scientific http://www.adeptscience.com List Archive: http://lists.adeptscience.co.uk/ --- Would you like this to come to a different email address? --- Simply leave the mailing list (see below) and re-join by sending a blank email from the new address to: or --- You are currently subscribed to mathcad as: /> To unsubscribe send a blank email to
Attachments:  collab - matrix expansion 01.mcd

Re: [mathcad] resizing a matrix/vector
Author: Tom Boni    Posted: Mon, 8 Sep 2008 15:11:52 -0700 (
This is a technique that I will have use for. Thanks! --- On Sun, 9/7/08, Radovan Omorjan wrote: > From: Radovan Omorjan /> > Subject: Re: [mathcad] resizing a matrix/vector > To: /> > Date: Sunday, September 7, 2008, 8:27 AM > Forgot to attach the file, sorry > > > What options are there for resizing a matrix/vector? > > > > For instance lets say I have a 1 x 9 vector and want > to make it 1 x 6 > or 1 x 12? > > > > Right now, I just create a new (empty) vector of the > desired size... > > > > Just thought I'd ask in case there is an > "on-the-fly" method that I > am not aware of... > > > > In many cases the elements of the new vector are the > same as elements > in the existing vector... > > > --- > The Mathcad List - Discussion, Support & News > Contributions: /> > Hosted by: Adept Scientific > http://www.adeptscience.com > List Archive: http://lists.adeptscience.co.uk/ > --- > Would you like this to come to a different email address? > --- > Simply leave the mailing list (see below) and re-join by > sending a blank email from the new address to: > or > --- > You are currently subscribed to mathcad as: > /> > To unsubscribe send a blank email to > /> --- The Mathcad List - Discussion, Support & News Contributions: /> Hosted by: Adept Scientific http://www.adeptscience.com List Archive: http://lists.adeptscience.co.uk/ --- Would you like this to come to a different email address? --- Simply leave the mailing list (see below) and re-join by sending a blank email from the new address to: or --- You are currently subscribed to mathcad as: /> To unsubscribe send a blank email to />

RE: [mathcad] resizing a matrix/vector
Author: Tom Boni    Posted: Mon, 8 Sep 2008 15:21:18 -0700 (
Philip, I think I understand your point. Isn't this why one needs to be sure that they haven't accidentally redefined their "variables" during the course of a calculation (?) Although, couldn't one argue that the x in F(x) is a "true" variable? Thanks again... --- On Sat, 9/6/08, Philip Oakley wrote: > From: Philip Oakley /> > Subject: RE: [mathcad] resizing a matrix/vector > To: /> > Date: Saturday, September 6, 2008, 3:36 PM > Tom, > > The hidden feature of MathCAD is that in reality it > doesn't have any > variables. It has named constants that exist for a part of > a page between > the point it is defined and the point that another of the > same name is > defined. > > The only 'unless' is that within a programme (with > the black bar and the > left pointing arrows) those variables are true variables > that can be > overwritten and are thrown away at the end of the > execution. > > So if you define > v:=stack(1,2,3,4,5,6,7,8,9) > then > v:submatrix(v,2,7,0,0) > > you now have two variables 'v' (both vectors) on > the page and if you type > "v=" and then drag it around, you will see the > two results depending on > where the "v=" is on the page. > > Also, if you have a set of indices 'index' to be > used to pull out and > re-order it you can use. you can even convert it to a > little programme if > needed. > > i:=0;..last(index) > v[i]:=v[(index[i])] > will also do it (I have closed the [] brackets subscripts, > shown :=, and the > range ;.. > > Hope that helps. > Philip > > -----Original Message----- > From: Tom Boni /> > Sent: 05 September 2008 8:11 PM > To: /> > Subject: [mathcad] resizing a matrix/vector > > > What options are there for resizing a matrix/vector? > > For instance lets say I have a 1 x 9 vector and want to > make it 1 x 6 or 1 x > 12? > > Right now, I just create a new (empty) vector of the > desired size... > > Just thought I'd ask in case there is an > "on-the-fly" method that I am not > aware of... > > In many cases the elements of the new vector are the same > as elements in the > existing vector... > > > > > --- > The Mathcad List - Discussion, Support & News > Contributions: /> > Hosted by: Adept Scientific > http://www.adeptscience.com > List Archive: http://lists.adeptscience.co.uk/ > --- > Would you like this to come to a different email address? > --- > Simply leave the mailing list (see below) and re-join by > sending a blank email from the new address to: > or > --- > You are currently subscribed to mathcad as: > /> > To unsubscribe send a blank email to > /> > > --- > The Mathcad List - Discussion, Support & News > Contributions: /> > Hosted by: Adept Scientific > http://www.adeptscience.com > List Archive: http://lists.adeptscience.co.uk/ > --- > Would you like this to come to a different email address? > --- > Simply leave the mailing list (see below) and re-join by > sending a blank email from the new address to: > or > --- > You are currently subscribed to mathcad as: > /> > To unsubscribe send a blank email to > /> --- The Mathcad List - Discussion, Support & News Contributions: /> Hosted by: Adept Scientific http://www.adeptscience.com List Archive: http://lists.adeptscience.co.uk/ --- Would you like this to come to a different email address? --- Simply leave the mailing list (see below) and re-join by sending a blank email from the new address to: or --- You are currently subscribed to mathcad as: /> To unsubscribe send a blank email to />

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