A function related with speed light and time

Hello dear friends, I need to write a function called Ltime that takes as input a row vector of distances in miles and returns two output arguments. The first output argument is a row vector of the corresponding time in minutes for light to travel each distance, it takes light a little over 8 minutes to travel from the sun to the earth which are 92.9 million miles apart. The second output argument is a vector of the inputs in kilometers. The speed of light is 300,000 km/s and a mile is 1,609 km.

Also I should this code for getting the function: [a,b]=Ltime([10,100,1000,10000]). Thank you!

[Walter Roberson]

Your code does not define A, B, C or D before the second line is executed . Are they functions that take no arguments? And then you overwrite the input M , and then you overwrite the four functions??

I am having trouble figuring out what anything in your function has to do with the assignment, with the exception that V=300000 looks like an approximation for the speed of light (which would normally be coded as c instead of V)

Answer 1

[William Rose]

@Lewis HC,

It is nice to see that you have made an attempt before posting your question.

@Walter Roberson is exactly right as usual.

You had the right idea when you wrote "[a,b]=Ltime([10,100,1000,10000])". Use a syntax like that in the funciton declaration (line 1).

Short version

function [a,b]=Ltime(M)
a=M*8.947e-8; 
b=M*1.609;
end

Longer version

function [a,b]=Ltime(M)
%LTIME returns light time in minutes, and distance in km.
%Input
%   M=vector of distances in miles
%Outputs
%   a=time in minutes for light to travel the distances in M
%   b=distances M, converted to km
c=2.9979e5;     %speed of light in km/s
b=M*1.6093;     %convert miles to km
a=b/(c*60);     %time in minutes
end

Note that 1.6093/(c*60)=8.948e-8, the constant in the short version of the function.

[Walter Roberson]

William note that this is a school assignment and you have provided complete commented code.

[Lewis HC]

Thank you very much dear friends, really, I love Matlab but there are small problems that confuse me sometimes, I thank you for your support and criticism, you are the best, thanks again

[William Rose]

@Lewis HC, you're welcome.

"there are small problems that confuse me sometimes"

I often feel the same way, and I bet most Matlab users do.

[William Rose]

@Walter Roberson, thank you for the feedback. Good point. I guess I was more helpful than I should have been because he showed his own code and his other idea. Which many people don't do.