text: r"""
  Basic tests of data access and computation for `SpaceCurve`
  
  Copyright
  ---------
  - This file is part of https://github.com/geomdata/gda-public/ 
  - 2015, 2016, 2017 by Geometric Data Analytics, Inc. (http://geomdata.com)
  - AGPL license. See `LICENSE` or https://github.com/geomdata/gda-public/blob/master/LICENSE
  
  Examples
  --------
  
  >>> from __future__ import print_function
  >>> from timeseries import SpaceCurve, curve_geometry
  >>> F = SpaceCurve.load("tests/spiral.csv")
  >>> F
  SpaceCurve with 126 entries and duration 625.000000000
  >>> for label in F.data.columns:
  ...     print(label)
  time
  pos_x
  pos_y
  pos_z
  quality
  >>> F[0]
  time       0.0
  pos_x      1.0
  pos_y      0.0
  pos_z      0.0
  quality   -1.0
  Name: 0, dtype: float64
  >>> time = F.data['time'].values
  >>> pos = F.data[['pos_x','pos_y','pos_z']].values
  >>> F.compute()
  >>> vel = F.info[['vel_x','vel_y','vel_z']].values
  >>> arclengthS = curve_geometry.secant_arclength(pos)
  
  
  """
  
  