astro plan:docs

- Index
- Modules

### Navigation

- next »
- « previous |
- astroplan v0.7 »
- Reference/API »
- AirmassConstraint

# AirmassConstraint

class `astroplan.``AirmassConstraint`(max=None, min=1, boolean_constraint=True)

  Bases: `astroplan.AltitudeConstraint`

  Constrain the airmass of a target.

  In the current implementation the airmass is approximated by the secant of the zenith angle.

  Note

  The `max` and `min` arguments appear in the order (max, min) in this initializer to support the common case for users who care about the upper limit on the airmass (`max`) and not the lower limit.

  Parameters
    max float or `None`

      Maximum airmass of the target. `None` indicates no limit.

    min float or `None`

      Minimum airmass of the target. `None` indicates no limit.

    boolean_contstraint bool

  Examples

  To create a constraint that requires the airmass be “better than 2”, i.e. at a higher altitude than airmass=2:

      AirmassConstraint(2)

  Methods Summary

  `compute_constraint`(times, observer, targets) | Actually do the real work of computing the constraint.

  Methods Documentation

  `compute_constraint`(times, observer, targets)

    Actually do the real work of computing the constraint. Subclasses override this.

    Parameters
      times `Time`

        The times to compute the constraint

      observer `Observer`

        the observaton location from which to apply the constraints

      targets sequence of `Target`

        The targets on which to apply the constraints.

    Returns
      constraint_result 2D array of float or bool

        The constraints, with targets along the first index and times along the second.