CLASSQ man page on Oracle

Man page or keyword search:  
man Server   33470 pages
apropos Keyword Search (all sections)
Output format
Oracle logo
[printable version]

classq.f(3)			    LAPACK			   classq.f(3)

       classq.f -

       subroutine classq (N, X, INCX, SCALE, SUMSQ)
	   CLASSQ updates a sum of squares represented in scaled form.

Function/Subroutine Documentation
   subroutine classq (integerN, complex, dimension( * )X, integerINCX,
       realSCALE, realSUMSQ)
       CLASSQ updates a sum of squares represented in scaled form.


	    CLASSQ returns the values scl and ssq such that

	       ( scl**2 )*ssq = x( 1 )**2 +...+ x( n )**2 + ( scale**2 )*sumsq,

	    where x( i ) = abs( X( 1 + ( i - 1 )*INCX ) ). The value of sumsq is
	    assumed to be at least unity and the value of ssq will then satisfy

	       1.0 .le. ssq .le. ( sumsq + 2*n ).

	    scale is assumed to be non-negative and scl returns the value

	       scl = max( scale, abs( real( x( i ) ) ), abs( aimag( x( i ) ) ) ),

	    scale and sumsq must be supplied in SCALE and SUMSQ respectively.
	    SCALE and SUMSQ are overwritten by scl and ssq respectively.

	    The routine makes only one pass through the vector X.


		     N is INTEGER
		     The number of elements to be used from the vector X.


		     X is COMPLEX array, dimension (N)
		     The vector x as described above.
			x( i )	= X( 1 + ( i - 1 )*INCX ), 1 <= i <= n.


		     INCX is INTEGER
		     The increment between successive values of the vector X.
		     INCX > 0.


		     SCALE is REAL
		     On entry, the value  scale	 in the equation above.
		     On exit, SCALE is overwritten with the value  scl .


		     SUMSQ is REAL
		     On entry, the value  sumsq	 in the equation above.
		     On exit, SUMSQ is overwritten with the value  ssq .

	   Univ. of Tennessee

	   Univ. of California Berkeley

	   Univ. of Colorado Denver

	   NAG Ltd.

	   September 2012

       Definition at line 107 of file classq.f.

       Generated automatically by Doxygen for LAPACK from the source code.

Version 3.4.2			Tue Sep 25 2012			   classq.f(3)

List of man pages available for Oracle

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
Vote for polarhome
Free Shell Accounts :: the biggest list on the net