Question

The geographic coordinate system is used to represent any location on Earth as a combination of latitude and longitude values. These values are angles that can be written in the decimal degrees (DD) form or the degree, minutes, seconds (DMS) form just like time. For example, 24.5° is equivalent to 24°30'00''. Write a MATLAB script that will prompt the user for an angle in DD form and will print in sentence format the same angle in DMS form. The script should error-check for invalid user input. The angle conversion is to be done by calling a separate function in the script.

Answer 1

Answer:

Here is the script:  

function dd = functionDMS(dd)  

prompt= 'Enter angle in DD form ';

dd = input(prompt)

while (~checknum(dd))

if ~checknum(dd)

error('Enter valid input ');

end

dd = input(prompt)

end  

degrees = int(dd)

minutes = int(dd - degrees)

seconds = ( dd - degrees - minutes / 60 ) * 3600  

print degrees

print minutes

print seconds

print dd

Explanation:

The script prompts the user to enter an angle in decimal degree (DD) form. Next it stores that input in dd. The while loop condition checks that input is in valid form. If the input is not valid then it displays the message: Enter valid input. If the input is valid then the program converts the input dd into degrees, minutes and seconds form. In order to compute degrees the whole number part of input value dd is used. In order to compute the minutes, the value of degrees is subtracted from value of dd. The other way is to multiply remaining decimal by 60 and then use whole number part of the answer as minutes. In order to compute seconds subtract dd , degrees and minutes values and divide the answer by 60 and multiply the entire result with 3600. At the end the values of degrees minutes and seconds are printed. In MATLAB there is also a function used to convert decimal degrees to degrees minutes and seconds representation. This function is degrees2dms.

Another method to convert dd into dms is:

data = "Enter value of dd"

dd = input(data)

degrees = fix(dd);

minutes = dd - degrees;

seconds = (dd-degrees-minutes/60) *3600;