Good afternoon,dear users.
I need to multiply a matrix with a vector and with other matrix again in R.
It looks like A^(-1,inverse matrix)*p(some random vector)*C (other matrix).
Where A is generated by formula (j^2H+k^2H-|j-k|^2H ),where j,k are rows and columns and H is a certain coefficient.
And the obtained vector to multiply by the matrix C(which is generated as A,but not inverse).
The obtained result is a vecor.
I would also like to change the dimensions of the matrix and vector.
May anybody to suggest me some code to generate a matrix and multiplication?
Thank you very much for your help.
Dear Valeriia Bondarenko
Take the following steps:
1. Using the matrix() function
2. data is the input vector that represents the matrix's elements.
3. The number of rows to be constructed is specified by nrow.
4. The number of columns to be formed is specified by ncol.
5. The logical value is specified by byrow. If TRUE, the matrix will be loaded one row at a time.
6. dimnames defines the names of rows and columns.
For matrices, R offers two multiplication operators. The first is represented by the symbol *, which is the same as a basic multiplication sign. This operation performs element-by-element multiplication up to and including matrices. The second operator, indicated by percent * percent, conducts matrix multiplication on the two matrices.
In R, you must use the matrix function to generate a matrix (). The vector's elements are passed as parameters to this matrix(). You must specify the number of rows and columns that you want in your matrix. Matrixes are ordered in column-wise order by default.
In R, for example, the matrix() function may be used to construct a matrix. For instance, the following code will generate a 3 by 3 matrix: matrix(3:11, nrow = 3, ncol = 3) Furthermore, vectors may be combined to form matrices.
I also recommend that you finish this tutorial: https://www.youtube.com/watch?v=8v9KQqokKVc
Kind Regards
Qamar Ul Islam
Qamar Ul Islam,thank you very much for your answer.
Could you tell me please,and I need to generate the matrix by following formula:
(j^2H+k^2H-ABS|j-k|^2H ),where j,k are rows and columns,H=0.6,inverse this matrix and after to multiply for some random vector,how i cn to describe this?
The dimension of matrix and vector is 50x50
Thanks a lot for your help
Use the %*% operator to do any matrix multiply operation. It does not matter if one of the operands is a vector.
Make sure R is using OpenBlas libraries. They improve the efficiency of matrix multiply .
Regards, Neville
Hi,Neville
Could you telle me please, by which function may Igenerate this matrix (j^2H+k^2H-ABS|j-k|^2H )?
Thank you very much
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