watex.utils.makeCoords#

watex.utils.makeCoords(reflong, reflat, nsites, *, r=45.0, utm_zone=None, step='1km', order='+', todms=False, is_utm=False, raise_warning=True, **kws)[source]#

Generate multiple stations coordinates (longitudes, latitudes) from a reference station/site.

One degree of latitude equals approximately 364,000 feet (69 miles), one minute equals 6,068 feet (1.15 miles), and one-second equals 101 feet. One-degree of longitude equals 288,200 feet (54.6 miles), one minute equals 4,800 feet (0.91 mile) , and one second equals 80 feet. Illustration showing longitude convergence. (1 feet ~=0.3048 meter)

Parameters:

  • reflong (float or string or list of [start, stop]) – Reference longitude in degree decimal or in DD:MM:SS for the first site considered as the origin of the landmark.

  • reflat (float or string or list of [start, stop]) – Reference latitude in degree decimal or in DD:MM:SS for the reference site considered as the landmark origin. If value is given in a list, it can containt the start point and the stop point.

  • nsites (int or float) – Number of site to generate the coordinates onto.

  • r (float or int) – The rotate angle in degrees. Rotate the angle features the direction of the projection line. Default value is 45 degrees.

  • step (float or str) – Offset or the distance of seperation between different sites in meters. If the value is given as string type, except the km, it should be considered as a m value. Only meters and kilometers are accepables.

  • order (str) – Direction of the projection line. By default the projected line is in ascending order i.e. from SW to NE with angle r set to 45 degrees. Could be - for descending order. Any other value should be in ascending order.

  • is_utm (bool,) – Consider the first two positional arguments as UTM coordinate values. This is an alternative way to assume reflong and reflat are UTM coordinates ‘easting’and ‘northing` by default. If utm2deg is False, any value greater than 180 degrees for longitude and 90 degrees for latitude will raise an error. Default is False.

  • utm_zone (string (##N or ##S)) – utm zone in the form of number and North or South hemisphere, 10S or 03N Must be given if utm2deg is set to True.

  • todms (bool) – Convert the degree decimal values into the DD:MM:SS. Default is False.

  • raise_warning (bool, default=True,) – Raises warnings if GDAL is not set or the coordinates accurately status.

  • kws (dict,) – Additional keywords of gistools.project_point_utm2ll().

Returns:

  • Tuple of generated projected coordinates longitudes and latitudes

  • either in degree decimals or DD (MM:SS)

Notes

The distances vary. A degree, minute, or second of latitude remains fairly constant from the equator to the poles; however a degree, minute, or second of longitude can vary greatly as one approaches the poles and the meridians converge.

References

https://math.answers.com/Q/How_do_you_convert_degrees_to_meters

Examples

>>> from watex.utils.coreutils import makeCoords
>>> rlons, rlats = makeCoords('110:29:09.00', '26:03:05.00',
...                                     nsites = 7, todms=True)
>>> rlons
... array(['110:29:09.00', '110:29:35.77', '110:30:02.54', '110:30:29.30',
       '110:30:56.07', '110:31:22.84', '110:31:49.61'], dtype='<U12')
>>> rlats
... array(['26:03:05.00', '26:03:38.81', '26:04:12.62', '26:04:46.43',
       '26:05:20.23', '26:05:54.04', '26:06:27.85'], dtype='<U11')
>>> rlons, rlats = makeCoords ((116.7, 119.90) , (44.2 , 40.95),
                                        nsites = 238, step =20. ,
                                        order = '-', r= 125)
>>> rlons
... array(['119:54:00.00', '119:53:11.39', '119:52:22.78', '119:51:34.18',
       '119:50:45.57', '119:49:56.96', '119:49:08.35', '119:48:19.75',
       ...
       '116:46:03.04', '116:45:14.43', '116:44:25.82', '116:43:37.22',
       '116:42:48.61', '116:42:00.00'], dtype='<U12')
>>> rlats
... array(['40:57:00.00', '40:57:49.37', '40:58:38.73', '40:59:28.10',
       '41:00:17.47', '41:01:06.84', '41:01:56.20', '41:02:45.57',
       ...
   '44:07:53.16', '44:08:42.53', '44:09:31.90', '44:10:21.27',
   '44:11:10.63', '44:12:00.00'], dtype='<U11')