---
name: "dlapy3"
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/dlapy3.f"
---

# dlapy3(3)

Part of [dlapy3.f(3)](/dlapy3.f/3.md).

## NAME

SRC/dlapy3.f

## SYNOPSIS

### Functions/Subroutines

double precision function **dlapy3** (x, y, z)\
 **DLAPY3** returns sqrt(x2+y2+z2).

## Function/Subroutine Documentation

### double precision function dlapy3 (double precision x, double precision y, double precision z)

**DLAPY3** returns sqrt(x2+y2+z2).

**Purpose:**

```
!>
!> DLAPY3 returns sqrt(x**2+y**2+z**2), taking care not to cause
!> unnecessary overflow and unnecessary underflow.
!>
```

**Parameters**

*X*

```
!>          X is DOUBLE PRECISION
!>
```

*Y*

```
!>          Y is DOUBLE PRECISION
!>
```

*Z*

```
!>          Z is DOUBLE PRECISION
!>          X, Y and Z specify the values x, y and z.
!>
```

**Author**

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Definition at line **67** of file **dlapy3.f**.

## Author

Generated automatically by Doxygen for LAPACK from the source code.