In a 2D orthogonal coordinate system where the distances between horizontal lines (say, along the x-axis) and vertical lines (say, along the y-axis) are not the same, you are dealing with a scaled coordinate system. This means that the unit distance in the x-direction is different from the unit distance in the y-direction.

To accurately calculate the distance between two points $(x_1, y_1)$ and $(x_2, y_2)$ in such a system, you need to account for the scaling factors along the axes.

Steps to calculate the distance:

1. Identify the scaling factors:
   Let $s_x$ be the scaling factor along the x-axis, and $s_y$ be the scaling factor along the y-axis. These represent the distances between consecutive grid lines in the x- and y-directions, respectively.

2. Transform the coordinates:
   Since the distances are scaled, you need to adjust the coordinates of the points by the respective scaling factors. The transformed coordinates will be:

   • For point $(x_1, y_1)$, the transformed coordinates are $\left( s_x \cdot x_1, s_y \cdot y_1 \right)$.
   • For point $(x_2, y_2)$, the transformed coordinates are $\left( s_x \cdot x_2, s_y \cdot y_2 \right)$.

3. Apply the distance formula:
   Now, use the standard Euclidean distance formula with the transformed coordinates: $d = \sqrt{(s_x \cdot (x_2 - x_1))^2 + (s_y \cdot (y_2 - y_1))^2}$ This formula accounts for the different distances between horizontal and vertical lines.

Example:

If the scaling factor along the x-axis is $s_x = 2$ and along the y-axis is $s_y = 3$, and you want to calculate the distance between points $(1, 2)$ and $(4, 6)$, the transformed points are:

• For $(1, 2)$: $(2 \cdot 1, 3 \cdot 2) = (2, 6)$.
• For $(4, 6)$: $(2 \cdot 4, 3 \cdot 6) = (8, 18)$.

The distance is: $d = \sqrt{(8 - 2)^2 + (18 - 6)^2} = \sqrt{6^2 + 12^2} = \sqrt{36 + 144} = \sqrt{180} \approx 13.42$

Would you like further details or any specific clarification?

5 Related Questions:

1. How do the scaling factors affect the slope of a line in such a system?
2. How can we use this formula in 3D with different scales along all three axes?
3. How does this system relate to affine transformations?
4. Can this concept be applied to map projections where scales vary in different directions?
5. How do the properties of geometric shapes change when subjected to different scaling along axes?

Tip:

Always check that the scaling factors are consistent with the physical or graphical system you're working with, as incorrect scaling can lead to inaccurate distance calculations.