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# Source : Point sources from arrays

Collections of point sources can be initialised through either a collection of arrays, or an astropy Table

```{code-cell} ipython3
import numpy as np
import astropy.table as table
from astropy import units as u

import scopesim

# how many stars
n = 200

# random coordinated in a 100 arcsec box
x, y  = 100 * np.random.random(size=(2, n)) - 50

# All stars reference the Vega spectrum
ref = np.zeros(n)      
# Each star is given a different weighting, i.e. magnitude
weight = 10**(-0.4*np.linspace(10, 20, n))

# Note: The Pyckles and SpeXtra libraries contain many more stellar and galactic spectra
vega = scopesim.source.source_templates.vega_spectrum(mag=20)
```

## astropy.Table

```{code-cell} ipython3
tbl = table.Table(names=["x", "y", "ref", "weight"],
                  data= [x,    y,   ref,   weight],
                  units=[u.arcsec, u.arcsec, None, None])

table_source = scopesim.Source(table=tbl, spectra=[vega])

table_source.plot()
```

## From loose arrays

```{code-cell} ipython3
point_source = scopesim.Source(spectra=[vega], x=x, y=y, ref=ref, weight=weight)

point_source.plot()
```