The function latLngDistanceMeter, present in vincenty.py, accepts two tuples as paramters where each tuple contains the coordinates

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Question:

The function latLngDistanceMeter, present in vincenty.py, accepts two tuples as paramters where each tuple contains the coordinates (latitude,longitude) of a point on the Earth and performs the vincenty calculation.

How can I Develop a function named buildingDistance that is passed two building IDs and determines the vincenty distance between two building IDs.

def latLngDistanceMeters(point1, point2):
"""
Vincenty's formula (inverse method) to calculate the distance (in
kilometers or miles) between two points on the surface of a spheroid

Doctests:
>>> vincenty((0.0, 0.0), (0.0, 0.0)) # coincident points
0.0
>>> vincenty((0.0, 0.0), (0.0, 1.0))
111.319491
>>> vincenty((0.0, 0.0), (1.0, 0.0))
110.574389
>>> vincenty((0.0, 0.0), (0.5, 179.5)) # slow convergence
19936.288579
>>> vincenty((0.0, 0.0), (0.5, 179.7)) # failure to converge
>>> boston = (42.3541165, -71.0693514)
>>> newyork = (40.7791472, -73.9680804)
>>> vincenty(boston, newyork)
298.396057
>>> vincenty(boston, newyork, miles=True)
185.414657
"""
import math

# WGS 84
a = 6378137 # meters
f = 1 / 298.257223563
b = 6356752.314245 # meters; b = (1 - f)a

MAX_ITERATIONS = 200
CONVERGENCE_THRESHOLD = 1e-12 # .000,000,000,001
# short-circuit coincident points
if point1[0] == point2[0] and point1[1] == point2[1]:
return 0.0

U1 = math.atan((1 - f) * math.tan(math.radians(point1[0])))
U2 = math.atan((1 - f) * math.tan(math.radians(point2[0])))
L = math.radians(point2[1] - point1[1])
Lambda = L

sinU1 = math.sin(U1)
cosU1 = math.cos(U1)
sinU2 = math.sin(U2)
cosU2 = math.cos(U2)

for iteration in range(MAX_ITERATIONS):
sinLambda = math.sin(Lambda)
cosLambda = math.cos(Lambda)
sinSigma = math.sqrt((cosU2 * sinLambda) ** 2 +
(cosU1 * sinU2 - sinU1 * cosU2 * cosLambda) ** 2)
if sinSigma == 0:
return 0.0 # coincident points
cosSigma = sinU1 * sinU2 + cosU1 * cosU2 * cosLambda
sigma = math.atan2(sinSigma, cosSigma)
sinAlpha = cosU1 * cosU2 * sinLambda / sinSigma
cosSqAlpha = 1 - sinAlpha ** 2
try:
cos2SigmaM = cosSigma - 2 * sinU1 * sinU2 / cosSqAlpha
except ZeroDivisionError:
cos2SigmaM = 0
C = f / 16 * cosSqAlpha * (4 + f * (4 - 3 * cosSqAlpha))
LambdaPrev = Lambda
Lambda = L + (1 - C) * f * sinAlpha * (sigma + C * sinSigma *
(cos2SigmaM + C * cosSigma *
(-1 + 2 * cos2SigmaM ** 2)))
if abs(Lambda - LambdaPrev) < CONVERGENCE_THRESHOLD:
break # successful convergence
else:
return None # failure to converge

uSq = cosSqAlpha * (a ** 2 - b ** 2) / (b ** 2)
A = 1 + uSq / 16384 * (4096 + uSq * (-768 + uSq * (320 - 175 * uSq)))
B = uSq / 1024 * (256 + uSq * (-128 + uSq * (74 - 47 * uSq)))
deltaSigma = B * sinSigma * (cos2SigmaM + B / 4 * (cosSigma *
(-1 + 2 * cos2SigmaM ** 2) - B / 6 * cos2SigmaM *
(-3 + 4 * sinSigma ** 2) * (-3 + 4 * cos2SigmaM ** 2)))
s = b * A * (sigma - deltaSigma)

return s

umich_buildings = [{
"address": "1000 Victors Way",
"id": "1000v",
"lat": 42.238815,
"lng": -83.732150,
"name": "1000 Victors Way"
},
{
"address": "1032 Greene Street Ann Arbor, MI 48109-1402",
"id": "grn",
"lat": 42.268264,
"lng": -83.747851,
"name": "1032 Greene Building"
},
{
"address": "523 South Division Street Ann Arbor, MI 48104",
"id": "523di",
"lat": 42.275507,
"lng": -83.744046,
"name": "523 South Division Building"
}]