Homework 4 Solution

Airports and Runways

Description

In this assignment (HW4), you will implement two programs that can be used to plan a flight. The first program called airport prints a detailed description of an airport including the names and lengths of its runways. The second program called distance computes and prints the distance between two airports. In a fictional scenario, a pilot who plans a trip could check the details of available runways at a given airport and compute the distances between airports.

This assignment will test your C++ proficiency in opening and reading text files, using strings, using STL containers, using STL algorithms, and implementing function objects.

Program specifications

airport

The airport program prints a description of an airport. It should read data from two text files containing information about Federal Aviation Administration (FAA) facilities and runways. The files Facilities.txt and Runways.txt are provided and contain a list of 19700 facilities (such as airports, heliports, seaplane bases) and 23595 runways located mostly in the United States, but also in remote locations. Each line in the Facilities.txt file contains the description of a facility (airport, heliport or seaplane base). The first part of the line contains the site number, a 10-character string that uniquely identifies the facility. The rest of the line contains other information, including the facility type, name, code, and position (latitude and longitude in various formats). For example, San Francisco International Airport has site number 02187.*A , type AIRPORT , code SFO, name SAN FRANCISCO INTL , latitude

135427.7000N and longitude 440551.5000W (expressed in seconds decimal). The positions of these fields in the line are:

- Site number:

- Type:
- Code:
- Name:
- Latitude (sec decimal):

characters 1-10

characters 12-24
characters 25-28
characters 131-180
characters 536-547

    • Longitude (sec decimal): characters 563-574 Other fields are not relevant to this assignment.

Each line in the Runways.txt file contains the description of a runway. The first part of the line contains the site number of the facility it belongs to (i.e. the 10-character string described above). The rest of the line contains other information about the runway, including its name and length (in feet). For example, runway 10L/28R of San Francisco International airport has site number 02187.*A , name 10L/28R and a length of 11870 ft. The positions of these fields in the line are:
- Site number:

- Name:
- Length:
characters 1-10

characters 14-20
characters 21-25

Other fields are not relevant to this assignment.

The airport program should read the code of an airport (e.g. SFO) as a command line argument. The program should then open and read the above text files, create appropriate Facility and Runway objects, and store them using STL vectors. The STL find_if algorithm should be used together with a function object Code defined in a file Code.h to find the airport having the given code. The program should then print the description of the airport (site number, code and name). The program should then search for all runways that belong to the identified airport. This search will use the STL stable_partition algorithm and a function object SiteNumber defined in the file SiteNumber.h . The program should then print a description of all the runways of the airport (site number, name and length).

Notes:

    • The airport code is entered as a command line argument.

    • If the airport code is not found (e.g. ABCD), the program should print

ABCD not found and exit.

    • If the airport code given is longer than 4 characters, the program should print
Airport code must be at most 4 characters and exit.

    • Some valid airport codes consist of 3 characters only.

You are given the files Facility.h and Runway.h which declare classes that represent facilities and runways respectively. You should not modify these files. You must create the files Facility.cpp and Runway.cpp to implement the member functions of the classes Facility and Runway . You are also given files testFacility.cpp and testRunway.cpp, which are used to test your implementation of the Facility and the Runway objects.
You must create the files Code.h and SiteNumber.h to define the corresponding function objects. The programs testCode.cpp and testSiteNumber.cpp are provided and should not be modified. You are also given the files gcdistance.h and gcdistance.cpp that include the implementation of the calculation of the distance between two locations on Earth specified by their latitudes and longitudes. These two files should not be modified.

distance

The distance program prints the distance between two airports. The airport codes are read from the command line arguments. The distance is printed in nautical miles, rounded to an integer. See the example output files for the output format.

Notes:

    • The airport codes are entered as command line arguments characters.

    • If any of the airport codes is not found (e.g. ABCD), the program should print

ABCD not found
and exit.

    • If any of the airport codes given is longer than 4 characters, the program should print
Airport code must be at most 4 characters and exit.

    • Some valid airport codes consist of 3 characters only.

Description of the Facility and Runway classes

Facility class

The member functions of the Facility class are defined as follows:

Facility(string s)

The constructor takes a single string argument. The argument s contains a full line read from
the Facilities.txt file. The constructor should initialize the data members of Facility
by selecting the appropriate substrings from the argument. The latitude and longitude fields
should be converted to double values using the convert_latitude and

convert_longitude member functions. The sign of the latitude_ and longitude_

data members should be determined by checking whether the latitude and longitude fields end
with N or S, and E or W respectively.

string site_number(void) const

This function returns the facility’s site number.

string type(void) const

This function returns the facility’s type.

string code(void) const

This function returns the facility’s code.

string name(void) const

This function returns the facility’s name.

double latitude(void) const

This function returns the latitude of the facility in degrees decimal. Latitudes in the southern hemisphere are negative numbers.

double longitude(void) const

This function returns the longitude of the facility in degrees decimal. Longitudes in the western hemisphere are negative numbers.

double distance(double lat, double lon) const

This function returns the distance in nautical miles between the facility and the position defined by (lat,lon) in degrees decimal. The implementation of this function uses the gcdistance function provided in files gcdistance.h and gcdistance.cpp .

double convert_latitude(string s) const

This function converts the string s representing a latitude in seconds decimal to a double value in degrees decimal. One degree is 3600 seconds. The sign of the result is positive if the string s
ends with N and negative if it ends with S . For example, the latitude represented by the string 135427.7000N should be converted to the value 37.6188

double convert_longitude(string s) const

This function converts the string s representing a longitude in seconds decimal to a double value in degrees decimal. One degree is 3600 seconds. The sign of the result is positive if the string s ends with E and negative if it ends with W . For example, the longitude represented by the string 440551.5000W should be converted to the value -122.3754 .

Runway class

The member functions of the Runway class are defined as follows:

Runway(string s)

The constructor takes a single string argument. The argument s contains a full line read from the Runways.txt file. The constructor should initialize the data members of Runway by selecting the appropriate substrings from the argument.

string site_number(void) const

This function returns the site number of the facility that the runway belongs to.

string name(void) const

This function returns the name of the runway.

int length(void) const

This function returns the length of the runway in ft.

int convert_length(string s) const

This function converts the string s representing a runway length to an int value in feet.

Function objects

Two function objects must be defined. The Code function object (to be defined in the file Code.h) is used to identify facilities having a given code. The SiteNumber function object (to be defined in the file SiteNumber.h) is used to identify either a Facility or a Runway having a given site number. Note that this requires the use of a template in the implementation of the SiteNumber function object. The programs testCode.cpp and testSiteNumber.cpp are provided to test the function objects, and should not be modified.

Test programs

The test programs testFacility.cpp, testRunway.cpp, testCode.cpp and testSiteNumber.cpp are provided and should not be modified. These programs will be used (with the corresponding input and output files) to test your implementations of the Facility and Runway classes and of the Code and SiteNumber function objects.



HW4 Assignment

Your task is to implement the files Facility.cpp , Runway.cpp , Code.h , SiteNumber.h , airport.cpp , distance.cpp and Makefile. All programs should build without warning on CSIF using the command
$ make

Do not use C++11 or C++14 or more recent C++ features in your source files. Use the g++ compiler with the –Wall option.

Test cases

Five test cases of the airport program are provided with corresponding output files. Shell script files named testairport1.sh to testairport5.sh are provided and include the invocation of the airport program with its command line arguments. The files testairport1.out to testairport5.out contain the corresponding output. Similar files are provided to test the distance program. Test output files for the programs testCode, testSiteNumber, testFacility and testRunway are also provided.

Examples of use

$ ./airport SFO

02187.*A    SFO    SAN FRANCISCO INTL
02187.*A    01L/19R 7650
02187.*A    01R/19L 8650
02187.*A    10L/28R 11870
02187.*A    10R/28L 11381
02187.*A    28X    0

$ ./airport SAN

02170.*A    SAN    SAN DIEGO INTL
02170.*A    09/27    9400

$ ./distance SAN SFO

SAN    - SFO    388 NM

$ ./distance SAN ORD

SAN    - ORD    1494 NM


Verify that your programs reproduce the tests exactly. Use the diff command to compare your output with the reference test output files. Note that other test files may also be used when grading your implementation.

Submission

Create a tar file named hw4.tar containing your Makefile and all the files needed to build the airport, distance, testFacility, testRunway, testCode, and testSiteNumber programs. In order to limit file size, do NOT include the files Facilities.txt and Runways.txt in your tar file. Submit your project using:

$ handin cs36b hw4 hw4.tar