csyl01()

subroutine csyl01	(	real	thresh,
		integer, dimension( 3 )	nfail,
		real, dimension( 2 )	rmax,
		integer, dimension( 2 )	ninfo,
		integer	knt
	)

CSYL01

Purpose:

 CSYL01 tests CTRSYL and CTRSYL3, routines for solving the Sylvester matrix
 equation

    op(A)*X + ISGN*X*op(B) = scale*C,

 where op(A) and op(B) are both upper triangular form, op() represents an
 optional conjugate transpose, and ISGN can be -1 or +1. Scale is an output
 less than or equal to 1, chosen to avoid overflow in X.

 The test code verifies that the following residual does not exceed
 the provided threshold:

    norm(op(A)*X + ISGN*X*op(B) - scale*C) /
        (EPS*max(norm(A),norm(B))*norm(X))

 This routine complements CGET35 by testing with larger,
 random matrices, of which some require rescaling of X to avoid overflow.

Parameters

[in]	THRESH	THRESH is REAL A test will count as "failed" if the residual, computed as described above, exceeds THRESH.
[out]	NFAIL	NFAIL is INTEGER array, dimension (3) NFAIL(1) = No. of times residual CTRSYL exceeds threshold THRESH NFAIL(2) = No. of times residual CTRSYL3 exceeds threshold THRESH NFAIL(3) = No. of times CTRSYL3 and CTRSYL deviate
[out]	RMAX	RMAX is DOUBLE PRECISION array, dimension (2) RMAX(1) = Value of the largest test ratio of CTRSYL RMAX(2) = Value of the largest test ratio of CTRSYL3
[out]	NINFO	NINFO is INTEGER array, dimension (2) NINFO(1) = No. of times CTRSYL where INFO is nonzero NINFO(2) = No. of times CTRSYL3 where INFO is nonzero
[out]	KNT	KNT is INTEGER Total number of examples tested.