What’s wrong with this coordinate again?
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This post was last edited by bei*ang0728 on 2019-12-19 02:55. Friends, please give some advice: these are the coordinate locations J6 (3559.467,8617.576), J8 (3357.483,8691.274), J9 (3314.746,8574.526), and J10 (3516.847,8510.074). When plotted according to the coordinates, it looks like this, but the plan shows it in a different way; even if the coordinates are rotated, these positioning points still don’t align. The surveying and mapping institute said there was no problem with the map. Could it be that I made a mistake in my drawing techniques? Marine friends offered guidance. I am extremely grateful.
First, it’s necessary to determine whether the coordinate systems of the two graphs are in the same coordinate system! The survey drawings have coordinate values at the four corner points, and the coordinate system and elevation system are indicated in the lower left corner; it is essential that these elements all be within the same coordinate system in order to ensure accurate comparisons! Otherwise, it will be either too far away or at the wrong angle. Because the origin positions of different coordinate systems are not exactly the same!
First, check the direction of the coordinate arrows on the maps from the surveying and mapping institute; they don’t necessarily all point to the right and upward
Why draw it by hand? Can’t you just copy it and draw on the base map?
That’s right, this issue has been clarified. The people from the surveying and mapping institute swapped XY, saying it was a software setting issue. Thank you
To add, XY are not swapped; rather, the X and Y coordinates used for measurement are reversed. In other words, the X direction refers to north-south, while the Y coordinate refers to east-west, which is why it seems as though the XY coordinates are swapped； There is also a more professional way of putting it: the XY coordinates we use represent the view of the Earth from the sky, but when making measurements, we look up at the sky from the ground, so they are reversed! But as long as the coordinate systems are in the same coordinate system, they can be fully aligned! :D
When entering coordinates in CAD, you enter y first and then x; your diagram has been mirrored along a 45° line