﻿Pnsw Method
Transforms a vector from an Earth-fixed geographic system to a space-fixed system

Namespace: ASCOM.Astrometry.NOVAS
Assembly: ASCOM.Astrometry (in ASCOM.Astrometry.dll) Version: 6.0.0.0 (6.1.1.2619)

# Syntax

C#
```public static void Pnsw(
double tjd,
double gast,
double x,
double y,
double[] vece,
ref double[] vecs
)```
Visual Basic
```Public Shared Sub Pnsw ( _
tjd As Double, _
gast As Double, _
x As Double, _
y As Double, _
vece As Double(), _
ByRef vecs As Double() _
)```
Visual C++
```public:
static void Pnsw(
double tjd,
double gast,
double x,
double y,
array<double>^ vece,
array<double>^% vecs
)```

#### Parameters

tjd
Type: System..::..Double
TT (or TDT) Julian date
gast
Type: System..::..Double
Greenwich apparent sidereal time, in hours.
x
Type: System..::..Double
Conventionally-defined X coordinate of rotational pole with respect to CIO, in arcseconds.
y
Type: System..::..Double
Conventionally-defined Y coordinate of rotational pole with respect to CIO, in arcseconds.
vece
Type: array<System..::..Double>[]()[][]
Vector in geocentric rectangular Earth-fixed system, referred to geographic equator and Greenwich meridian.
vecs
Type: array<System..::..Double>[]()[][]%
OUT: Vector in geocentric rectangular space-fixed system, referred to mean equator and equinox of J2000.0.

# Remarks

Transforms a vector from an Earth-fixed geographic system to a space-fixed system based on mean equator and equinox of J2000.0; applies rotations for wobble, spin, nutation, and precession.