Part 2: ZIP code look up and distance calculation

As part of an Open Data Policy, the U.S. Government released a large number of datasets to

conduct research, develop web and mobile applications, design data visualizations [1]. Among these

is a dataset that provides geographic coordinates for U.S. 5 digit ZIP codes. For this assignment,

we will be using a slightly improved version of the ZIP dataset available at [2]. For each ZIP code,

this dataset lists geographic coordinates (latitude and longitude), city, state, and county. Our goal

is to use available data to develop a new data product that would allow users not only to query

and search the existing data source but also to access additional functionality such as computing

the distance between two locations.

Write a program that would allow users to lookup locations by ZIP code, lookup ZIP codes by city

and state, and determine the distance between two locations designated by their ZIP codes. The

program interacts with the user by printing a prompt and allowing them to enter commands until

they enter 'end' at which point the program prints Done and finishes. If an invalid command is

entered, the program prints Invalid command, ignoring and is ready to take the next command.

The following commands are recognized:

1. loc allows the user to enter a ZIP code, then looks up city, state, county, and geographic

coordinates that correspond to the ZIP code and prints this data; If a ZIP code is invalid or

not found in the dataset, the program prints a error message instead. Look at the following

sample output:

Command ('loc', 'zip', 'dist', 'end') => loc

loc

Enter a ZIP code to lookup => 12180

12180

ZIP code 12180 is in Troy, NY, Rensselaer county,

coordinates: (04240'25.32"N,07336'31.65"W)

Note that coordinates are enclosed in parentheses and are separated by a comma; each coordinate

is printed in integer degrees (three digits), followed by the

symbol, integer minutes

(two digits), followed by the ' character, integer and fractional seconds (two integer and two

decimal digits), followed by the " character, and a cardinal direction letter (N, S, W, or E)

with no spaces anywhere in the coordinate representation.

2. zip allows the user to enter city and state, then looks up the ZIP code or codes (some cities

have more than one) which correspond to this location and prints them; if city and/or state

are invalid or not found in the dataset, it prints an error message instead.

Command ('loc', 'zip', 'dist', 'end') => zip

zip

Enter a city name to lookup => troY

troY

Enter the state name to lookup => ny

ny

The following ZIP code(s) found for Troy, NY: 12179, 12180, 12181, 12182, 12183

3. dist allows the user to enter two ZIP codes and computes the geodesic distance between the

location coordinates ; if any of the ZIP codes entered is invalid or not found in the dataset,

it prints a corresponding error message instead.

Command ('loc', 'zip', 'dist', 'end') => dist

dist

Enter the first ZIP code => 19465

19465

Enter the second ZIP code => 12180

12180

The distance between 19465 and 12180 is 201.88 miles

4. end stops fetching new commands from the user and ends the program

The utility module provided for this part of homework will give you some help. It provides a

function read_zip_all() that returns a list each element of which is, in turn, a list that contains

data about one zip code. Try the following:

import hw4_util

zip_codes = hw4_util.read_zip_all()

print(zip_codes[0])

print(zip_codes[4108])

would give:

['00501', 40.922326, -72.637078, 'Holtsville', 'NY', 'Suffolk']

['12180', 42.673701, -73.608792, 'Troy', 'NY', 'Rensselaer']

Note that the data on a particular ZIP code has the following fields in order: zip code (string),

latitude (float degrees), longitude (float degrees), city (string), state (string), and county (strings).

Implementation Details

You will need to define two functions that should strictly follow specifications outlined below:

1. zip_by_location(zip_codes, location) which finds the ZIP code for a given location.

Parameters:

zip_codes a list of ZIP codes data in the format, returned by read_zip_all()

location a two-element tuple where the first element is the city name and the second element

is the state abbreviation, e.g. ('trOy', 'nY'). Both elements are string values. City names

and state abbreviations can be written using any case or a mixture of lower and upper case.

Return value:

A list which contains ZIP code or codes for the specified location. Each ZIP code is a string

value. If the location is invalid, an empty list is returned.

E.g., ['12179', '12180', '12181', '12182', '12183']

2. location_by_zip(zip_codes, code) which finds location information corresponding to the

specified ZIP code.

Parameters:

zip_codes a list of ZIP codes and associated data in the format, returned by read_zip_all()

code ZIP code as a string value, e.g. '12180'.

Return value:

A five-element tuple ()latitude, longitude, city, state, county). Latitude and longitude

are in fractional degrees (floating point values). All other elements are string values.

E.g., (42.673701, -73.608792, 'Troy', 'NY', 'Rensselaer')

It is required that you implement functions according to specifications given above. You are also

expected to define other functions, as necessary. You need to determine which functions to define

and to design their specifications yourself, following the example we gave above for the two required

functions. Do not forget to include function specifications as comments right above the functions

definition in your code. Avoid copying and pasting repeated pieces of code. Those should be

factored out as functions. You may lose points for excessive duplication of code.

Hints and Helps

Formatting your output is a big part of this program. Here are a few hints.

1. The

symbol can be generated using another escape character similar to ' or '\t'. To

generate the

, use \xb0. Just like the tab and the newline, this is a single character.

2. When printing out the location, there is a tab character at the start of the second line before

coordinates.

3. if you want to print leading 0s before an integer, use the {:0Nd} where N is the total number

of spaces you want the integer to occupy. So a format of :07d will use 7 spaces to print your

integer, padding the front of the integer with 0s. I.e.

print("{:07d}".format(7))

will give

0000007

4. You will need to manage the latitude and longitude to convert among representations. In

particular, you need to convert the fractional degrees in the zip code list to degrees, minutes,

seconds. There are 60 minutes in a degree and 60 seconds in a minute. When you convert,

all of your latitudes and longitudes should be positive. Instead, use east (E) and west (W)

designators of longitude; and north (N) and south (S) designators for latitude. Negative

longitudes are west, positive are east. Negative latitudes are south, positives are north. In

bath cases, a latitude or longitude of 0 (the equator or the prime meridian, respectively) do

not have a designator.

5. The distance between two points on the surface of Earth uses a simplified haversine formula

for arc length on a sphere. You should implement Eq. 1 which assumes the Earth to be

spherical. This formula gives the shortest surface distance d as-the-crow-flies, ignoring

Earths relief.

latitude = latitude2 latitude1

longitude = longitude2 longitude1

a = sin2

latitude

2

+ cos(latitude1) cos(latitude2) sin2

longitude

2

d = 2R arcsin

a

(1)

Where R = 3959.191 miles is the radius of the Earth and all angle measurements are in

radians (the zip code data gives latitude and longitude in degrees).

Sample Output

Below is an example output that demonstrates program features:

Command ('loc', 'zip', 'dist', 'end') => loc

loc

Enter a ZIP code to lookup => 12180

12180

ZIP code 12180 is in Troy, NY, Rensselaer county,

coordinates: (04240'25.32"N,07336'31.65"W)

Command ('loc', 'zip', 'dist', 'end') => loc

loc

Enter a ZIP code to lookup => 1946

1946

Invalid or unknown ZIP code

Command ('loc', 'zip', 'dist', 'end') => loc

loc

Enter a ZIP code to lookup => 19465

19465

ZIP code 19465 is in Pottstown, PA, Chester county,

coordinates: (04011'30.87"N,07539'55.12"W)

Command ('loc', 'zip', 'dist', 'end') => loc

loc

Enter a ZIP code to lookup => 00000

00000

Invalid or unknown ZIP code

Command ('loc', 'zip', 'dist', 'end') => loc

loc

Enter a ZIP code to lookup => ksahdkja

ksahdkja

Invalid or unknown ZIP code

Command ('loc', 'zip', 'dist', 'end') => dist

dist

Enter the first ZIP code => 19465

19465

Enter the second ZIP code => 12180

12180

The distance between 19465 and 12180 is 201.88 miles

Command ('loc', 'zip', 'dist', 'end') => dist

dist

Enter the first ZIP code => 12180

12180

Enter the second ZIP code => 12180

12180

The distance between 12180 and 12180 is 0.00 miles

Command ('loc', 'zip', 'dist', 'end') => dist

dist

Enter the first ZIP code => 12180

12180

Enter the second ZIP code => 55499

55499

The distance between 12180 and 55499 cannot be determined

Command ('loc', 'zip', 'dist', 'end') => zip

zip

Enter a city name to lookup => troY

troY

Enter the state name to lookup => ny

ny

The following ZIP code(s) found for Troy, NY: 12179, 12180, 12181, 12182, 12183

Command ('loc', 'zip', 'dist', 'end') => zip

zip

Enter a city name to lookup => Amsterdam

Amsterdam

Enter the state name to lookup => NL

NL

No ZIP code found for Amsterdam, NL

Command ('loc', 'zip', 'dist', 'end') => help

help

Invalid command, ignoring

Command ('loc', 'zip', 'dist', 'end') => END

END

Done

When you have tested your code, please submit it as hw4Part2.py. Be sure to use the correct

filename or Submitty will not be able to grade your submission.

References

[1] Data.gov: The home of the U.S. Governments open data, 2018, Accessed on: Feb. 23, 2018.

[Online]. Available: https://www.data.gov/

[2] Download: Zip code latitude longitude city state county csv, San Diego, CA, USA,

2018, Accessed on: Feb. 23, 2018. [Online]. Available: https://www.gaslampmedia.com/

download-zip-code-latitude-longitude-city-state-county-csv/

Utility:

This is a utility module for Homework#4 in CSCI 1100 Fall 2015

For part 2, use the read_zip_all function to read the pokemon appearance information as follows:

zip_codes = hw4_util.read_zip_all() print(zip_codes[4108])

""" def read_zip_all(): i = 0 header = [] zip_codes = [] zip_data = [] skip_line = False # http://notebook.gaslampmedia.com/wp-content/uploads/2013/08/zip_codes_states.csv for line in open('zip_codes_states.csv').read().split(" "): skip_line = False m = line.strip().replace('"', '').split(",") i += 1 if i == 1: for val in m: header.append(val) else: zip_data = [] for idx in range(0,len(m)): if m[idx] == '': skip_line = True break if header[idx] == "latitude" or header[idx] == "longitude": val = float(m[idx]) else: val = m[idx] zip_data.append(val) if not skip_line: zip_codes.append(zip_data) return zip_codes

if __name__ == "__main__":

zip_codes = read_zip_all() print(zip_codes[4108])