nrm2 - nrm2: || x ||_2

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real(wp)functiondnrm2(integern,real(wp),dimension(*)x,integerincx)DNRM2Purpose: DNRM2 returns the euclidean norm of a vector via the function name, so that DNRM2 := sqrt( x'*x ) ParametersN N is INTEGER number of elements in input vector(s) X X is DOUBLE PRECISION array, dimension ( 1 + ( N - 1 )*abs( INCX ) ) INCX INCX is INTEGER, storage spacing between elements of X If INCX > 0, X(1+(i-1)*INCX) = x(i) for 1 <= i <= n If INCX < 0, X(1-(n-i)*INCX) = x(i) for 1 <= i <= n If INCX = 0, x isn't a vector so there is no need to call this subroutine. If you call it anyway, it will count x(1) in the vector norm N times. Author Edward Anderson, Lockheed Martin Date August 2016 Contributors: Weslley Pereira, University of Colorado Denver, USA FurtherDetails: Anderson E. (2017) Algorithm 978: Safe Scaling in the Level 1 BLAS ACM Trans Math Softw 44:1--28 https://doi.org/10.1145/3061665 Blue, James L. (1978) A Portable Fortran Program to Find the Euclidean Norm of a Vector ACM Trans Math Softw 4:15--23 https://doi.org/10.1145/355769.355771 real(wp)functiondznrm2(integern,complex(wp),dimension(*)x,integerincx)DZNRM2Purpose: DZNRM2 returns the euclidean norm of a vector via the function name, so that DZNRM2 := sqrt( x**H*x ) ParametersN N is INTEGER number of elements in input vector(s) X X is COMPLEX*16 array, dimension (N) complex vector with N elements INCX INCX is INTEGER, storage spacing between elements of X If INCX > 0, X(1+(i-1)*INCX) = x(i) for 1 <= i <= n If INCX < 0, X(1-(n-i)*INCX) = x(i) for 1 <= i <= n If INCX = 0, x isn't a vector so there is no need to call this subroutine. If you call it anyway, it will count x(1) in the vector norm N times. Author Edward Anderson, Lockheed Martin Date August 2016 Contributors: Weslley Pereira, University of Colorado Denver, USA FurtherDetails: Anderson E. (2017) Algorithm 978: Safe Scaling in the Level 1 BLAS ACM Trans Math Softw 44:1--28 https://doi.org/10.1145/3061665 Blue, James L. (1978) A Portable Fortran Program to Find the Euclidean Norm of a Vector ACM Trans Math Softw 4:15--23 https://doi.org/10.1145/355769.355771 real(wp)functionscnrm2(integern,complex(wp),dimension(*)x,integerincx)SCNRM2Purpose: SCNRM2 returns the euclidean norm of a vector via the function name, so that SCNRM2 := sqrt( x**H*x ) ParametersN N is INTEGER number of elements in input vector(s) X X is COMPLEX array, dimension (N) complex vector with N elements INCX INCX is INTEGER, storage spacing between elements of X If INCX > 0, X(1+(i-1)*INCX) = x(i) for 1 <= i <= n If INCX < 0, X(1-(n-i)*INCX) = x(i) for 1 <= i <= n If INCX = 0, x isn't a vector so there is no need to call this subroutine. If you call it anyway, it will count x(1) in the vector norm N times. Author Edward Anderson, Lockheed Martin Date August 2016 Contributors: Weslley Pereira, University of Colorado Denver, USA FurtherDetails: Anderson E. (2017) Algorithm 978: Safe Scaling in the Level 1 BLAS ACM Trans Math Softw 44:1--28 https://doi.org/10.1145/3061665 Blue, James L. (1978) A Portable Fortran Program to Find the Euclidean Norm of a Vector ACM Trans Math Softw 4:15--23 https://doi.org/10.1145/355769.355771 real(wp)functionsnrm2(integern,real(wp),dimension(*)x,integerincx)SNRM2Purpose: SNRM2 returns the euclidean norm of a vector via the function name, so that SNRM2 := sqrt( x'*x ). ParametersN N is INTEGER number of elements in input vector(s) X X is REAL array, dimension ( 1 + ( N - 1 )*abs( INCX ) ) INCX INCX is INTEGER, storage spacing between elements of X If INCX > 0, X(1+(i-1)*INCX) = x(i) for 1 <= i <= n If INCX < 0, X(1-(n-i)*INCX) = x(i) for 1 <= i <= n If INCX = 0, x isn't a vector so there is no need to call this subroutine. If you call it anyway, it will count x(1) in the vector norm N times. Author Edward Anderson, Lockheed Martin Date August 2016 Contributors: Weslley Pereira, University of Colorado Denver, USA FurtherDetails: Anderson E. (2017) Algorithm 978: Safe Scaling in the Level 1 BLAS ACM Trans Math Softw 44:1--28 https://doi.org/10.1145/3061665 Blue, James L. (1978) A Portable Fortran Program to Find the Euclidean Norm of a Vector ACM Trans Math Softw 4:15--23 https://doi.org/10.1145/355769.355771

nrm2 - nrm2: || x ||_2

Functions real(wp) function dnrm2 (n, x, incx) DNRM2 real(wp) function dznrm2 (n, x, incx) DZNRM2 real(wp) function scnrm2 (n, x, incx) SCNRM2 real(wp) function snrm2 (n, x, incx) SNRM2