Vector norm of an array of vectors in MATLAB

by

You can compute the norm of each column or row of a matrix yourself by using element-wise arithmetic operators and functions defined to operate over given matrix dimensions (like SUM and MAX). Here’s how you could compute some column-wise norms for a matrix M:

twoNorm = sqrt(sum(abs(M).^2,1)); %# The two-norm of each column
pNorm = sum(abs(M).^p,1).^(1/p);  %# The p-norm of each column (define p first)
infNorm = max(M,[],1);            %# The infinity norm (max value) of each column

These norms can easily be made to operate on the rows instead of the columns by changing the dimension arguments from ...,1 to ...,2.

More Related Contents:

  1. Generate a matrix containing all combinations of elements taken from n vectors
  2. Linear indexing, logical indexing, and all that
  3. Repeat copies of array elements: Run-length decoding in MATLAB
  4. Using transpose versus ctranspose in MATLAB
  5. Creating Indicator Matrix
  6. Array of Matrices in MATLAB
  7. how to replicate an array
  8. How do I iterate through each element in an n-dimensional matrix in MATLAB?
  9. Is indexing vectors in MATLAB inefficient?
  10. How do I remove elements at a set of indices in a vector in MATLAB?
  11. Excel-VBA – Insert new first column in datafield array without loops or API calls
  12. Element-wise array replication in Matlab
  13. arrayfun can be significantly slower than an explicit loop in matlab. Why?
  14. How do I do multiple assignment in MATLAB?
  15. MATLAB adding array elements iteratively: time behavior
  16. How do i define a structure in Matlab
  17. Element-wise array replication according to a count [duplicate]
  18. Convert a matrix to a 1 dimensional array
  19. Why is reshape so fast? (Spoiler: Copy-on-Write)
  20. Multiply a 3D matrix with a 2D matrix
  21. What is the advantage of linspace over the colon “:” operator?
  22. How do I compare all elements of two arrays?
  23. In an assignment A(:) = B, the number of elements in A and B must be the same
  24. How to use cell arrays in Matlab?
  25. How to get mean, median, and other statistics over entire matrix, array or dataframe?
  26. Combining matrices into an array in R
  27. Is there anything like deal() for normal MATLAB arrays? [duplicate]
  28. Vector multiplication using MATMUL in Fortran
  29. convert string to number array in matlab
  30. Efficiently compute a 3D matrix of outer products – MATLAB

Leave a Comment