/// <summary>
/// Constructor with data to init variables and the name of the passband
/// </summary>
/// <param name="row">Field info from query (DataRow)</param>
/// <param name="band">Passband name (string)</param>
public Band(DataRow row, string band)
{
if ("ugriz".IndexOf(band.ToLower()) < 0)
{
throw new ApplicationException("Parameter 'band' is invalid! Should be one of u,g,r,i or z...");
}
this.filter = band;
this.node = (double)row["node"];
this.incl = (double)row["incl"];
string postfix = "_" + band;
//this.a = (double)row["a"+postfix];
//this.b = (double)row["b"+postfix];
//this.c = (double)row["c"+postfix];
//this.d = (double)row["d"+postfix];
//this.e = (double)row["e"+postfix];
//this.f = (double)row["f"+postfix];
// this Convert is used because only dr8 gives problem it has float values
// otherwise simple (double) cast works for all others
this.a = Convert.ToDouble(row["a" + postfix]);
this.b = Convert.ToDouble(row["b" + postfix]);
this.c = Convert.ToDouble(row["c" + postfix]);
this.d = Convert.ToDouble(row["d" + postfix]);
this.e = Convert.ToDouble(row["e" + postfix]);
this.f = Convert.ToDouble(row["f" + postfix]);
this.pixperdeg = 9088;
this.wcs = this.Wcs();
}
/// <summary>
/// Get WCS at any pixel in the image
/// </summary>
/// <param name="crpix1">pixel coord 1 (double)</param>
/// <param name="crpix2">pixel coord 2 (double)</param>
/// <returns>WCS</returns>
public WCS Wcs(double crpix1, double crpix2)
{
SdssCoord[] corner;
center = CoordsAtPix(crpix1, crpix2);
corner = CornerCoords();
double mu, nu, ra, dec;
// build linear eqns and solve for affine transform
double mumu = 0, nunu = 0, munu = 0, ramu = 0, ranu = 0, decmu = 0, decnu = 0;
for (int i = 0; i < corner.Length; i++)
{
mu = corner[i].mu - center.mu;
nu = corner[i].nu - center.nu;
ra = corner[i].ra - center.ra;
dec = corner[i].dec - center.dec;
// increment
mumu += mu * mu;
munu += mu * nu;
nunu += nu * nu;
ramu += ra * mu;
ranu += ra * nu;
decmu += dec * mu;
decnu += dec * nu;
}
double p, q, s, r;
SolveSym2D(mumu, munu, nunu, ramu, ranu, out p, out q);
SolveSym2D(mumu, munu, nunu, decmu, decnu, out s, out r);
WCS wcs = new WCS();
wcs.EPOCH = "J2000";
wcs.CTYPE2 = "DEC--TAN";
wcs.CTYPE1 = "RA---TAN";
wcs.CUNIT1 = "deg";
wcs.CUNIT2 = "deg";
wcs.NAXIS1 = this.npix1;
wcs.NAXIS2 = this.npix2;
wcs.CRPIX1 = crpix1 + 0.5; // different SDSS vs FITS convention (Steve Kent)
wcs.CRPIX2 = crpix2 + 0.5; // -"-
wcs.CRVAL1 = center.ra;
wcs.CRVAL2 = center.dec;
wcs.CD1_1 = p * b + q * e;
wcs.CD1_2 = s * b + r * e;
wcs.CD2_1 = p * c + q * f;
wcs.CD2_2 = s * c + r * f;
// john's suggestions for a fix
double scale = Math.Cos(center.dec * Math.PI / 180);
wcs.CD1_1 *= scale;
wcs.CD1_2 *= scale;
return(wcs);
}
