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algorithmmatrixtraversalazimuth

Traverse matrix in a direction specified by azimuth

Traverse matrix in a direction specified by azimuth.

So I have a 2D matrix and an azimuth. What I want to do is traverse the matrix in that direction. From that azimuth I can derive a line equation.

Now I want to traverse the matrix in that direction of line. So in this case the 1st block I want to read info from is market as 1 then 2 and so on. (the values in the matrix right now are just to represent the order in which they are accessed)

https://i.sstatic.net/DPI9v.png

Let’s say if the line derived from azimuth goes as shown in the figure below then the matrix should be traverse from left to right.

https://i.sstatic.net/0D63q.png

If the problem is not clear please ask any question and I will explain further. Thanks for your time.

Solution

  • Label cell in row i column j by i * sin(a) + j * cos(a). Then traverse in ascending order of these labels. Assuming in your first example a = 45° and in the second a = 0°.

    So for your first example, sin(a) = cos(a) = sqrt(0.5). The calculated labels are the values in your figure multiplied by sqrt(2).

    For your second example, sin(a) = 0; cos(a) = 1 and you get the same values as in your figure.