---
name: "dlctsx.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/dlctsx.f"
---

# dlctsx.f(3)

## NAME

TESTING/EIG/dlctsx.f

## SYNOPSIS

### Functions/Subroutines

logical function **dlctsx** (ar, ai, beta)\
 **DLCTSX**

## Function/Subroutine Documentation

### logical function dlctsx (double precision ar, double precision ai, double precision beta)

**DLCTSX**

**Purpose:**

```
!>
!> This function is used to determine what eigenvalues will be
!> selected.  If this is part of the test driver DDRGSX, do not
!> change the code UNLESS you are testing input examples and not
!> using the built-in examples.
!>
```

**Parameters**

*AR*

```
!>          AR is DOUBLE PRECISION
!>          The numerator of the real part of a complex eigenvalue
!>          (AR/BETA) + i*(AI/BETA).
!>
```

*AI*

```
!>          AI is DOUBLE PRECISION
!>          The numerator of the imaginary part of a complex eigenvalue
!>          (AR/BETA) + i*(AI).
!>
```

*BETA*

```
!>          BETA is DOUBLE PRECISION
!>          The denominator part of a complex eigenvalue
!>          (AR/BETA) + i*(AI/BETA).
!>
```

**Author**

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Definition at line **64** of file **dlctsx.f**.

## Author

Generated automatically by Doxygen for LAPACK from the source code.