Dimensions of matrix-vector linear algebra

Similar Questions

• Matrix - vector lines and columns

  M1 (3,2) gives the element of line 3, column 2

  M1 (2) gives the second row of a matrix (as a vector line)

  Is there a way to return a column (other than transpose, store again and using the method above on the transposed matrix)?

  Tim Wessman wrote:
  

  Assuming that first here...

  Col(M1,1)

  Row(M1,1)

  @ Tim,.

  As Mmmm - created a post on the 39gii and commented on a post on the 39gii, this one is perhaps more likely to be on the 39gii?

  I think that your presumption re - expresses my presumption that the 39gii becomes brother forgot the premium?

  @ Mmmm.

  Try M1 (-c), where C is desired column number. For example M1(-2) for column 2.

• point 64 FFT

  Hello Sir,

  I want to know how to calculate the FFT for 64 points in LabLIEW. There are 64 entries which are complex numbers. My computaton throughout a series of blocks that are given below: -.

  1 stage input block

  FFT 2 stage-8 points

  Unit step 3-multiplier

  4 step 8-point FFT

  block scene-output 5.

  The FFT 8 points calculates the FFT of the first 8 samples then next 8 and so on...

  Most of the people a FFT in LabVIEW calculation using FFT VI (it accepts the complex numbers).  However, if you need to do this for a homework and show the algorithm, LabVIEW has all the functions of matrix and linear algebra to do this.  For more information, see Help.

• Solve linear equations - Block tridiagonal matrix

  Hello

  I developed a vi that can be used to solve tridiagonal systems by block of equations by Thomas algorithm. These systems are usually in the finite differences method used to solve equations in partial derivatives.

  For iterations of 1000 times, its time is ~ 500ms. Now, I want to finish the work within 100ms. is possible to improve the performance?

  Thanks, Jong Hyun

  For details of the Thomas algorithm, please see wikipedia Web page, http://en.wikipedia.org/wiki/Thomas_algorithm. Note that it describes how to solve tridiagonal linear equations, but same logic can be applied to block tridiagonal equations.

  * If you use the vi sparse SLE of analysis multi-hearts and Sparse Matrix Toolkit, the elapsed time is 450 ms ~

  LabVIEW basic/full/pro all use Intel MKL library for linear algebra on MS Windows and Linux.  Intel MKL designed to be very fast for large matrices and breaking a problem given out to take advantage of the different levels of cache. Linear algebra calls go through several levels of functions, including size controls, if any, and may allocate memory for the workspace each call, before finally calculate the result.  This overload problem is evident when the matrix is so small (3 x 3).

  I coded matrix-matrix, versions multiply, matrix-vector multiply, and matrix opposite in the case of 3 x 3 explicitly in soil using the structure in place and full indexation (no loops, all scalar operations).  This eliminates the overhead of controls and allows better and placeness.  This brings your reference point down for ~ 70ms on my machine.  Unfortunately this requires significant code changes if you change the block size, but it provides good performance.

  "I think that, if I can save each submatrix conversely in the first round and use several times, then speed will be better."

  I agree.  You should be able to calculate the most sweeping toward the front of the algorithm and simply replace the submatrices changed and still solve before.  This may mean re - organize the variables to have the submatrices updated or modified down to the right of the input matrix.

  -Jim

• Matrix multiplication: line 1 d vector * vector 3-3

  I tried to implement the matrix multiply: vector line 1 d * 3 - on - 3 vector in Labview, such as [1 2 3] * [1-2-1; 3 2 4; 5 7 8].

  But it does not seem easy to do.

  If I use the feature matrix-transfer table table of vector line 1-d matrix, he was always transferred to matrix column 1 d vector.

  In my view, it is also not convenient initialize a 1 d array line too.

  I am new to Labview, someone here could help me?

  Thank you very much!

  Huati wrote:

  "Leave the vector as a simple table 1 d." -whatever that means? Table can multiply?

  Use theAxB.vi mathematics of «...» Linear algebra Palette".»

  For example, the following code performs ' V' x matrix ' and 'matrix vector x. See the online help for more details.

  

• How to divide each unique number in a matrix by the number with an index in another matrix?

  Hello

  Basically, the calculation, I tried to do is called "dividing element by element". It is a transaction between two matrices with few passes and lines. The result matrix also has the same demension and each element is obtained by dividing the element with the same index in a matrix of the element with the index even in a different matrix. for examlpe,.

  A = [2 4 6

  3 9 6]

  B = [2 2 3

  3 3 2]

  the result will be

  C = [1, 2-2

  1 3 3]

  Is there an easy way to do another going out each element using the table to index?

  Thank you very much

  Hao Liu

  Use the 2D tables instead of the matrix data type, then just use a simple primitive division. the operation will be done by item automatically.

  

  (Generally you should always use table 2D instead of the special matrix data type. The matrix data type is most useful for linear algebra)

  (Die, he must be very careful, for example, if you multiply two 2D tables, you get a multiplication of element by element, but if you do the same operation on two matrices, LabVIEW will substitute for a real matrix multiplication, which is not the same. For the division, it seems that the matrices are divided piece-by-piece, so it might work for you directly. You should just be aware that the matrices are often treated differently. "They are a very special type of data).

• 3D display matrix image RGB (from MATLAB) in Labview

  Hello. I try to display the RGB 3 dimensions image matrix / table (from MATLAB) in LabVIEW. MATLAB returns a matrix 3D with RGB data, but it seems that LabVIEW takes only the 2D matrices. Is there anyway to display the image in labview?

  Thank you!

  .. and here's the example code (matlab and labview). Yesterday, I didn't have access to my computer.

  Best regards

  K

• Large cropping complicated vector files

  Hi everyone, I'm looking for help please.

  I'm new to illustrator who moved just from PC to Mac and CoreDraw to illustrator. I have a design work for the moment, but I am struggling to perform the tasks that I could about Corel. Basically, I want to crop an image, so that I can work on a section of it and delete everything else. I did some reading and understanding the culture issue is a common source of frustration for many but I am sure (hope) that there is a work around. I see clipping masks can be used, but they do not actually delete the Junk section. My problem is that the project that I'm getting is extremely large and complicated. It is a model which is about 8 metres by 6 metres, made up of vectors, and due to the size I reduced it to 1/100 to make it feasible. I'm going to do the piece as a whole as I apply a distortion effect to the entire organization, which is the reason for which I've upgraded to a powerful mac to make it faster.

  I have applied the Warp effect to the model but now want to be able to break the image up into panels for printing. Once I divided it into sections I can then expand back to 1:1 scale. I can't use photoshop because of the extreme size and I also want to keep the image as a vector because it is what the printer.

  One of the forums I've read has suggested creating a clipping mask and flatten transparency. This get the desired cropping effect, but the file with that I find myself behaves strangely. It wobbles when I move my mouse and vectors (a model of many irregular circles) appear to have changed.

  Be able to perform a crop is very important for the work I do and which is always on a large scale. Not only for the work I do now but in the future to be able to select a section of the image to send to the printer to make samples to show customers. I'm really looking forward to get to grips with Illustrator would be so grateful if someone could shine a light on a solution. Thanks in advance for your comments - Matt

  Looking at your art file I do not understand why it is bog down your machine...

  When I need create files that will be printed, for a business see the banner, or building signage, I build it on a smaller scale to avoid the problems you described. The printer must be able to resize to the proper output scale. The great thing about vector art is that it fits any size and keep all the lines clean and design elements. There is no need to build the actual size, that it will be printed. In the same way, you can print a section of art for you or your client at any level you want. Simply select the level you want in the print dialog box.

  To fix your file, try these 2 methods:

  Method 1:

  Create your art on a smaller scale and apply your effect of deformation.

  Select it and go: OBJECT / LARGER APPEARANCE. This should Flatten all applied effects and turn it into a single vector object.

  Save this art flattened under a separate file. Create a master document, and then go FILE / PLACE. Make sure it is LINKED and not INTEGRATED. Put it in as many times as you want, isolate each part of the image with a clipping mask, depending on the needs. Scale and print to whatever size you need.

  Method 2: Try to go from VECTOR to RASTER and VECTOR back. I had a similar problem, and it worked for me...

  Create your art on a smaller scale and apply your effect of deformation. Select it and copy it to the Clipboard.

  Note the dimensions of the vector art and create a PSD document that has the same size. It must be high ground, so if your vector art is 20 x 20 cm, the DPI of your PSD document should be at least 300. I would like to try 600 or even 1200.

  Paste your art in the PSD doc and save. (PSD, PNG or JPEG)

  Make a new Illustrator of the file, and then go to FILE / PLACE and place your PSD file in Illustrator. Keep it selected.

  Then go: WINDOW / Image Trace. You will probably get a warning about the size of the file but ignore it.
  Make sure that the Mode is black and white. Click on the Preview button and play with the settings until it looks good. That could never happen but at least you can say you tried. Once it looks good, go: OBJECT / EXPAND... and make sure that the objects and filling are selected. Press OK and cultures and adapt the new art to the needs. Send to the printer and have a beer.

• Why objects copied from illustrator vector cc do not stay the same size when pasted in pho

  I think that the problem started with the latest updates. Work normal flow of copy and paste no longer functions properly.

  Photshop changes the dimensions of the vector illustrations copied from illustrator and pasted in photoshop.

  If I start with a 6 x 6, vector shape in illustrator, then select copy, I should be able to enter in photoshop, select file and then new.

  and the document should automatically extract the dimensions of the Clipboard. For some reason any 6 "x 6" opens a 0.6 x 0.6 in document.

  Even if I manually change the document to 6 in. x 6 in., another thing I copy for more than 6 x 6 gets its dimensions changed to fit inside the illustrator document. I cannot copy and paste a 10 x 2 vector in 6 "x 6" document without changing the dimensions of photoshop

  If it fits inside the document. Any ideas on how to fix? Thank you.

  Hi Kelly,

  I think a number of things are colliding together. Looks like your main concern is that pasted files are to be resized to fit existing document limits, correct?

  There is an option in the preferences to disable this behavior. Do you know if you have this option unchecked

  

  Kind regards

  Steve

• limitations of memory of empty matrices

  Hi all

  I am using the Toolbox multi-hearts and empty matrices in order to create a n x n matrix with n = 1048576 identity. However, I get a memory error. No appears not the goal of this toolkit to store empty matrices using techniques of storage memory? I would like to prémultiplier a vector of n x 1 by an n x n diagonal matrix. Someone at - it alternative approaches?

  You use the plain (= not are rare) matrix tools (just optimized for multi-hearts).

  The (rare) special matrix to create is located in the subpalette "Sparse Linear Algebra". It has a different icon.

• calculate the scalar product

  Hi all

  hope that everyone else is doing great! I have a question about a problem that was asked to do. It says I have to calculate the scalar product, so I wonder if I just did? The constraints are that one way is to make ite with only discreet from the digital palette functions and the other functions of the range of linear algebra matrix. So I just hope that it is the right way to do it.

  Thank you

  Because in the dark ages, we had no linear algebra nice and convenient functions, you should know how to do it "manually". This is the point of most of the homework problems. To make you understand the concept then you know what it really means and the implementation to let you know how do it yourself.

  Just like in the dark ages we didn't have Google, so we used these buildings called libraries. And you looked up things in these large big cabinets full of drawers that had hundreds of cards in them. And you had to know the Dewey decimal system.

• multiplication of matrices

  HI, I would ask how to perform muptiplication matrix 10 x 10 with table (do not use linear algebra)...
  AxB = C (A, B, C all 10 x 10). How can I do this?  Many thanks for any help

  If you remember your secondary algebra, then it should be a very easy process to treat two 2D arrays of (I was going to say 'floats', but they could be integers) numbers as if they were a matrix and simply to perform the operation.  Have loops to auto-index through the two tables and relevant table of the functions (big hint - such that transpose) make it easy to do this in a very compact way.  Of course, if you've ever learned about matrices and how to manipulate them, it will be more complicated...

  Just thinking, you should be able to do it with two nested for loops, a matrix function and two digital functions.  For extra credit, you can add a Boolean test (followed by a Case statement that gives an Error Message If the test fails) to ensure that the two tables have a compatible size.

  Bob Schor

• Mutliplyng a table 1 d

  I tried a few methods and searched I just can't understand it.

  I am multiplying one table in itself and receive the 2D Board logic.

  I tried a while loop and multplying each elemnt by a full line/colum then build table, does not work.

  I've tried a few others with table to initialize and replace, shift, matrix conversion register and multiplying etc.  just does not work.

  any suggestions?

  My fault.  My linear algebra is not what it was I suppose.  Try this out...

  

• Is it possible to name a range of cells?

  Among the first large improvements in VisiCalc - surely there are some of you who remember VisiCalc - was the opportunity to name a range of cells. He came close to making VisiCalc a practical digital version of linear algebra. This ability is present in number?

  By the numbers, you usually break your work in relatively small, thin tables special.  Each column of each table behaves like a named range.  Each line does.  In other words, you can reference each line or each column by "name", which is the value in the header row at the top or left column header. Give it a try!

  SG

  P.S. on the Mac, this becomes more obvious if under the numbers > preferences you check "user as labels header names.  In iOS names (labels view by default).  However, even with this preference is disabled, you can enter the name in formulas.

• Ammeter reports an incorrect value

  I resolve this circuit with the method by mesh currents. I just installed NI MultiSim, and I expect to use to check my answers in school this semester. The first problem was the solution to the back of the book, so I decided to try Multisim for this purpose. After solving the circuit by hand (twice, I messed up my linear algebra) I plugged in the MultiSim circuit. The ammeter and the multimeter declare a value of 4.815 kA. The text book and my calculations return a value of 6.25 amps. I tried everything I could think of, nothing helps. I'm doing something wrong? Is the method by currents of mesh trumped by another tool of the analysis that I do not know? Please help me, I would like to be able to get instant feedback on my homework. Thank you

  Rewire your connections to R3, R4 and ground. They did not "connections." There is no point of connection about to mass. If you drag R4 to the right, you will see that it is not connected to R3 even if there is a connection point. Perhaps it's second nature to me, but I've always done my junction connections tick at least one of the grids of the component. It seems that there may be a problem any trying to make a second connection to the right of the element.