lapack_qr_f32

void lapack_qr_f32(const float * A, int m, int n, float * Q, float * R, int * info)

source edit

Single-precision reduced (thin) QR decomposition.

Computes $A = Q R$ where $Q$ is $m \times k$ with orthonormal columns and $R$ is $k \times n$ upper-triangular, $k = \min(m, n)$ . Internally calls sgeqrf_ to produce Householder reflectors then sorgqr_ to materialise $Q$ .

Math

$A = Q R, \;\; Q^T Q = I_k$

References

LAPACK sgeqrf_ + sorgqr_.

Parameters

Aconst float*

Row-major

m \times n

input.

m, nint

Matrix dimensions.

Qfloat*

Output orthonormal-columns matrix, shape

m \times k

(row-major).

Rfloat*

Output upper-triangular matrix, shape

k \times n

(row-major).

infoint*

LAPACK status word.

lapack_qr_f32

void lapack_qr_f32(const float * A, int m, int n, float * Q, float * R, int * info)

source edit

Single-precision reduced (thin) QR decomposition.

Math

$A = Q R, \;\; Q^T Q = I_k$

References

LAPACK sgeqrf_ + sorgqr_.

Parameters

Aconst float*

Row-major

m \times n

input.

m, nint

Matrix dimensions.

Qfloat*

Output orthonormal-columns matrix, shape

m \times k

(row-major).

Rfloat*

Output upper-triangular matrix, shape

k \times n

(row-major).

infoint*

LAPACK status word.