Question

Hi any help is appreciated! I am using C++.

The Julian Day Number (JDN) is a sequential count of days since the beginning of the Julian Period. Day number zero corresponds to 1 January 4713 BCE. As a result of calendar reform in the 16th Century, we will only be computing day numbers since 15 October 1582 (which was the first day of the modern Gregorian calendar, having day number 2299161). 1 January 2001 was day number 2451911.

To compute the JDN for a specific date, we need its month number (an integer between 1 and 12, where January = 1, February = 2, etc.), day (an integer between 1 and 31), and year (a four-digit integer). The JDN is calculated with the following formulas, using only integer arithmetic:

a ← [ ( 14 − month ) / 12 ] { Note: [ a / b ] means integer quotient only — no remainders or decimals! }

m ← ( month − 3 ) + ( 12 × a )

y ← year + 4800 − a

leap_days ← [ y / 4 ] − [ y / 100 ] + [ y / 400 ]

jdn ← day + [ ( ( 153 × m ) + 2 ) / 5 ] + ( 365 × y ) + leap_days − 32045

1. Using the formulas provided above, compute the JDN by hand for the following dates: 15 October 1582, 1 January 2001, and your instructor’s birthday. Show all work (i.e., show each formula in the calculation sequence with numbers replacing the variables, though you may want to use a calculator to help with the arithmetic) and check your results.

2. Create an IPO chart for a program that prompts the user to input a date as a month, day and year, then computes and displays the corresponding JDN. (Do this step, and the one that follows, before you start writing any source code.)

3. Create a table of test data with five dates, other than then ones used in Step #1. Choose a wide variety of dates that might help expose errors in your coding — e.g., use various months and days, along with a selection of years that are and are not leap years.

4. Write the program described in Step #2 in C++. Your program must separate input, processing, and output into at least three independent modules that are called in sequence by the main module. The user should be prompted as in the sample below, and your program should match the sample format as closely as possible (the underlined numbers in bold are examples of inputs made by the user — your program will not underline the user’s inputs or show them in bold):



Enter a month number (Jan=1, Feb=2, etc.): 6


Enter a day number (1..31) : 1


Enter a year using four digits : 1972



The JDN for 6/1/1972 is 2441470

Answer 1

C++ Program

#include<iostream> using namespace std; // function declaration void inputMDY(int&, int&, int&); // INPUT unsigned int calculateJDN(int, int, int); // PROCESSING void printJDN(int,int,int,unsigned int); // OUTPUT // main function int main() { // declare the variables int month = 0; int day = 0; int year = 0; unsigned int JDN = 0; // call the inputMDY() function // to input the values from the user inputMDY(month, day, year); // process the input to calculate JDN JDN = calculateJDN(month, day, year); // print the JDN cout << endl; printJDN(month,day,year,JDN); } // function to input the day, month and year // and return the same using call be reference // parameters to the function void inputMDY(int &m, int &d, int &y) { cout << "Enter a month number (Jan=1, Feb=2, etc.): "; cin >> m; cout << "Enter a day number (1..31) : "; cin >> d; cout << "Enter a year using four digits : "; cin >> y; } // function to calculate the Julian day number and return it unsigned int calculateJDN(int m, int d, int y) { // declare the JDN variable to store the result unsigned int JDN = 0; // perform the intermediate calculations int a = (14-m)/12; m = (m-3) + (12*a); y = y + 4800 - a; int leap_days = (int)(y/4) - (int)(y/100) + (int)(y/400); // do the main calculation and save the result in variable JDN JDN = (unsigned int)d+(( (int)((153*m) + 2 )/5 )+ (365*y) + leap_days - 32045); // return the result return JDN; } // function to print the JDN with date void printJDN(int m,int d,int y,unsigned int JDN) { cout << "The JDN for " << m << "/" << d <<"/" << y << " is: " << JDN << endl; }

OUTPUT