svdvals Interface
-
- experimental
- 22 statements
- Source File
public interface svdvals
Computes the singular values of a real or complex 2d matrix.
(Specification)
Summary
Function interface for computing the array of singular values from the singular value decomposition
of a real or complex 2d matrix.
Description
This interface provides methods for computing the singular values a 2d matrix.
Supported data types include real and complex. The function returns a real array of
singular values, with size [min(m,n)].
Note
The solution is based on LAPACK's singular value decomposition *GESDD methods.
Example
real(sp) :: a(2,3), s(2)
a = reshape([3,2, 2,3, 2,-2],[2,3])
s = svdvals(A)
print *, 'singular values = ',s
Functions
private module function stdlib_linalg_svdvals_c(a, err) result(s)
Summary
Compute singular values from the singular-value decomposition of a matrix .
Description
This function returns the array of singular values from the singular value decomposition of a real
or complex matrix .
param: a Input matrix of size [m,n]. param: err [optional] State return flag.
Return value
param: s real array of size [min(m,n)] returning a list of singular values.
Arguments
| Type | Intent | Optional | Attributes | Name | ||
|---|---|---|---|---|---|---|
| complex(kind=sp), | intent(in), | target | :: | a(:,:) |
Input matrix A[m,n] |
|
| type(linalg_state_type), | intent(out), | optional | :: | err |
[optional] state return flag. On error if not requested, the code will stop |
Return Value real(kind=sp), allocatable, (:)
Array of singular values
private module function stdlib_linalg_svdvals_d(a, err) result(s)
Summary
Compute singular values from the singular-value decomposition of a matrix .
Description
This function returns the array of singular values from the singular value decomposition of a real
or complex matrix .
param: a Input matrix of size [m,n]. param: err [optional] State return flag.
Return value
param: s real array of size [min(m,n)] returning a list of singular values.
Arguments
| Type | Intent | Optional | Attributes | Name | ||
|---|---|---|---|---|---|---|
| real(kind=dp), | intent(in), | target | :: | a(:,:) |
Input matrix A[m,n] |
|
| type(linalg_state_type), | intent(out), | optional | :: | err |
[optional] state return flag. On error if not requested, the code will stop |
Return Value real(kind=dp), allocatable, (:)
Array of singular values
private module function stdlib_linalg_svdvals_s(a, err) result(s)
Summary
Compute singular values from the singular-value decomposition of a matrix .
Description
This function returns the array of singular values from the singular value decomposition of a real
or complex matrix .
param: a Input matrix of size [m,n]. param: err [optional] State return flag.
Return value
param: s real array of size [min(m,n)] returning a list of singular values.
Arguments
| Type | Intent | Optional | Attributes | Name | ||
|---|---|---|---|---|---|---|
| real(kind=sp), | intent(in), | target | :: | a(:,:) |
Input matrix A[m,n] |
|
| type(linalg_state_type), | intent(out), | optional | :: | err |
[optional] state return flag. On error if not requested, the code will stop |
Return Value real(kind=sp), allocatable, (:)
Array of singular values
private module function stdlib_linalg_svdvals_z(a, err) result(s)
Summary
Compute singular values from the singular-value decomposition of a matrix .
Description
This function returns the array of singular values from the singular value decomposition of a real
or complex matrix .
param: a Input matrix of size [m,n]. param: err [optional] State return flag.
Return value
param: s real array of size [min(m,n)] returning a list of singular values.
Arguments
| Type | Intent | Optional | Attributes | Name | ||
|---|---|---|---|---|---|---|
| complex(kind=dp), | intent(in), | target | :: | a(:,:) |
Input matrix A[m,n] |
|
| type(linalg_state_type), | intent(out), | optional | :: | err |
[optional] state return flag. On error if not requested, the code will stop |
Return Value real(kind=dp), allocatable, (:)
Array of singular values