---
name: "zdrot.f"
section: "3"
platform: "linux"
package: "lapack-doc"
version: "3.12.1-2"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/zdrot.f"
---

# zdrot.f(3)

## NAME

BLAS/SRC/zdrot.f

## SYNOPSIS

### Functions/Subroutines

subroutine **zdrot** (n, zx, incx, zy, incy, c, s)\
 **ZDROT**

## Function/Subroutine Documentation

### subroutine zdrot (integer n, complex\*16, dimension( \* ) zx, integer incx, complex\*16, dimension( \* ) zy, integer incy, double precision c, double precision s)

**ZDROT**

**Purpose:**

```
!>
!> Applies a plane rotation, where the cos and sin (c and s) are real
!> and the vectors cx and cy are complex.
!> jack dongarra, linpack, 3/11/78.
!>
```

**Parameters**

*N*

```
!>          N is INTEGER
!>           On entry, N specifies the order of the vectors cx and cy.
!>           N must be at least zero.
!>
```

*ZX*

```
!>          ZX is COMPLEX*16 array, dimension at least
!>           ( 1 + ( N - 1 )*abs( INCX ) ).
!>           Before entry, the incremented array ZX must contain the n
!>           element vector cx. On exit, ZX is overwritten by the updated
!>           vector cx.
!>
```

*INCX*

```
!>          INCX is INTEGER
!>           On entry, INCX specifies the increment for the elements of
!>           ZX. INCX must not be zero.
!>
```

*ZY*

```
!>          ZY is COMPLEX*16 array, dimension at least
!>           ( 1 + ( N - 1 )*abs( INCY ) ).
!>           Before entry, the incremented array ZY must contain the n
!>           element vector cy. On exit, ZY is overwritten by the updated
!>           vector cy.
!>
```

*INCY*

```
!>          INCY is INTEGER
!>           On entry, INCY specifies the increment for the elements of
!>           ZY. INCY must not be zero.
!>
```

*C*

```
!>          C is DOUBLE PRECISION
!>           On entry, C specifies the cosine, cos.
!>
```

*S*

```
!>          S is DOUBLE PRECISION
!>           On entry, S specifies the sine, sin.
!>
```

**Author**

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Definition at line **97** of file **zdrot.f**.

## Author

Generated automatically by Doxygen for LAPACK from the source code.