- #1
MasterX
- 51
- 0
I hope I am posting in the right section.
Up to today I was assuming that Earth is a sphere, and I was using the spherical coordinates to convert longitude/latitude to x/y. But, I wanted to use a more accurate transformation, and I wanted to calculate x/y by considering the actual shape of the planet. Thus, I found that 1 degree of latitude is equal to 111km or 60 nautical miles. One degree of longitude, is equal to the same distance times the cosine of the latitude. Therefore, I can easily compute the x,y coordinates of all the points, if I set one point to be the origin.
Once I have the x,y coordinates of all the points, I compare them. To my surprise the coordinates of these points do not only differ in magnitude but sometimes in sign. More importantly, the relative difference between two points is not the same for these two methods.
Can someone explain to me why I am getting this awkward results. Is there a logic behind this counter intuitive result?
Thank you.
Up to today I was assuming that Earth is a sphere, and I was using the spherical coordinates to convert longitude/latitude to x/y. But, I wanted to use a more accurate transformation, and I wanted to calculate x/y by considering the actual shape of the planet. Thus, I found that 1 degree of latitude is equal to 111km or 60 nautical miles. One degree of longitude, is equal to the same distance times the cosine of the latitude. Therefore, I can easily compute the x,y coordinates of all the points, if I set one point to be the origin.
Once I have the x,y coordinates of all the points, I compare them. To my surprise the coordinates of these points do not only differ in magnitude but sometimes in sign. More importantly, the relative difference between two points is not the same for these two methods.
Can someone explain to me why I am getting this awkward results. Is there a logic behind this counter intuitive result?
Thank you.
Last edited: