3d distance calculations with GeoDjango

Question

I am using

• python 2.7.12
• django 1.10.6
• postgreSQL 9.5.6
• postGIS 2.2.2

First question

I ne

Answer 1

** python 3.7, Django 2.2.10

some useful functions ive written to help me with lat/lon coordinates in applications

from django.contrib.gis.geos import Point
from django.contrib.gis.measure import Distance


def get_point(lat, lon):
    try:
        lat = float(lat)
        lon = float(lon)
        if lat and lon:
            return Point(x=float(round(lon, 6)), y=float(round(lat, 6)), srid=4326)
        else:
            return None
    except Exception:
        return None


def get_point_to_point_distance(point_one, point_two, measurement_unit="mile"):
    return Distance(**{measurement_unit: point_one.distance(point_two)})

where measurement_unit can be any of the following:

    STANDARD_UNIT = "m"
    UNITS = {
        'chain': 20.1168,
        'chain_benoit': 20.116782,
        'chain_sears': 20.1167645,
        'british_chain_benoit': 20.1167824944,
        'british_chain_sears': 20.1167651216,
        'british_chain_sears_truncated': 20.116756,
        'cm': 0.01,
        'british_ft': 0.304799471539,
        'british_yd': 0.914398414616,
        'clarke_ft': 0.3047972654,
        'clarke_link': 0.201166195164,
        'fathom': 1.8288,
        'ft': 0.3048,
        'german_m': 1.0000135965,
        'gold_coast_ft': 0.304799710181508,
        'indian_yd': 0.914398530744,
        'inch': 0.0254,
        'km': 1000.0,
        'link': 0.201168,
        'link_benoit': 0.20116782,
        'link_sears': 0.20116765,
        'm': 1.0,
        'mi': 1609.344,
        'mm': 0.001,
        'nm': 1852.0,
        'nm_uk': 1853.184,
        'rod': 5.0292,
        'sears_yd': 0.91439841,
        'survey_ft': 0.304800609601,
        'um': 0.000001,
        'yd': 0.9144,
    }

    # Unit aliases for `UNIT` terms encountered in Spatial Reference WKT.
    ALIAS = {
        'centimeter': 'cm',
        'foot': 'ft',
        'inches': 'inch',
        'kilometer': 'km',
        'kilometre': 'km',
        'meter': 'm',
        'metre': 'm',
        'micrometer': 'um',
        'micrometre': 'um',
        'millimeter': 'mm',
        'millimetre': 'mm',
        'mile': 'mi',
        'yard': 'yd',
        'British chain (Benoit 1895 B)': 'british_chain_benoit',
        'British chain (Sears 1922)': 'british_chain_sears',
        'British chain (Sears 1922 truncated)': 'british_chain_sears_truncated',
        'British foot (Sears 1922)': 'british_ft',
        'British foot': 'british_ft',
        'British yard (Sears 1922)': 'british_yd',
        'British yard': 'british_yd',
        "Clarke's Foot": 'clarke_ft',
        "Clarke's link": 'clarke_link',
        'Chain (Benoit)': 'chain_benoit',
        'Chain (Sears)': 'chain_sears',
        'Foot (International)': 'ft',
        'German legal metre': 'german_m',
        'Gold Coast foot': 'gold_coast_ft',
        'Indian yard': 'indian_yd',
        'Link (Benoit)': 'link_benoit',
        'Link (Sears)': 'link_sears',
        'Nautical Mile': 'nm',
        'Nautical Mile (UK)': 'nm_uk',
        'US survey foot': 'survey_ft',
        'U.S. Foot': 'survey_ft',
        'Yard (Indian)': 'indian_yd',
        'Yard (Sears)': 'sears_yd'
    }