LAPACK 3.11.0 LAPACK: Linear Algebra PACKage
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## ◆ icamax()

 integer function icamax ( integer N, complex, dimension(*) CX, integer INCX )

ICAMAX

Purpose:
`    ICAMAX finds the index of the first element having maximum |Re(.)| + |Im(.)|`
Parameters
 [in] N ``` N is INTEGER number of elements in input vector(s)``` [in] CX ` CX is COMPLEX array, dimension ( 1 + ( N - 1 )*abs( INCX ) )` [in] INCX ``` INCX is INTEGER storage spacing between elements of CX```
Further Details:
```     jack dongarra, linpack, 3/11/78.
modified 3/93 to return if incx .le. 0.
modified 12/3/93, array(1) declarations changed to array(*)```

Definition at line 70 of file icamax.f.

71*
72* -- Reference BLAS level1 routine --
73* -- Reference BLAS is a software package provided by Univ. of Tennessee, --
74* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
75*
76* .. Scalar Arguments ..
77 INTEGER INCX,N
78* ..
79* .. Array Arguments ..
80 COMPLEX CX(*)
81* ..
82*
83* =====================================================================
84*
85* .. Local Scalars ..
86 REAL SMAX
87 INTEGER I,IX
88* ..
89* .. External Functions ..
90 REAL SCABS1
91 EXTERNAL scabs1
92* ..
93 icamax = 0
94 IF (n.LT.1 .OR. incx.LE.0) RETURN
95 icamax = 1
96 IF (n.EQ.1) RETURN
97 IF (incx.EQ.1) THEN
98*
99* code for increment equal to 1
100*
101 smax = scabs1(cx(1))
102 DO i = 2,n
103 IF (scabs1(cx(i)).GT.smax) THEN
104 icamax = i
105 smax = scabs1(cx(i))
106 END IF
107 END DO
108 ELSE
109*
110* code for increment not equal to 1
111*
112 ix = 1
113 smax = scabs1(cx(1))
114 ix = ix + incx
115 DO i = 2,n
116 IF (scabs1(cx(ix)).GT.smax) THEN
117 icamax = i
118 smax = scabs1(cx(ix))
119 END IF
120 ix = ix + incx
121 END DO
122 END IF
123 RETURN
124*
125* End of ICAMAX
126*
integer function icamax(N, CX, INCX)
ICAMAX
Definition: icamax.f:71
real function scabs1(Z)
SCABS1
Definition: scabs1.f:46
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