MATLAB: How to find distance between two points

distance

Hai,

I need to find the distance between two points in the figure, which I have plotted. Is there any function in matlab that could find the distance between two points. Looking for your reply.

BSD

Best Answer

You can use the pdist function in the Statistics Toolbox:

e.g: distance between points (0,0) and (2,1)

>> X = [0,0;2,1];
>> d = pdist(X,'euclidean')
d =
    2.2361

Related Solutions

MATLAB: Find the Euclidean distance

sqrt((x2-x1).^2 + (y2-y1).^2)

MATLAB: Distance between one point and the next of a list of points

Try this:

XY = [0  0;
	1  0;
	2  0;
	3  0;
	0 -1;
	1 -1;
	2 -1;
	3 -1]
consecutiveDistances = sqrt((x(2:end) - x(1:end-1)) .^ 2 + (y(2:end) - y(1:end-1)) .^ 2)

You'll see

consecutiveDistances =

3.1623

Another nice function you might want to know about, if you have the Statistics and Machine Learning Toolbox, is pdist2(). You can use pdist2(XY, XY) tol give distances between every point and every point in a 2-D array:

XY = [0  0;
	1  0;
	2  0;
	3  0;
	0 -1;
	1 -1;
	2 -1;
	3 -1]
distances = pdist2(XY, XY)

You'll see:

distances =

0 1 2 3 1 1.4142 2.2361 3.1623

1 0 1 2 1.4142 1 1.4142 2.2361

2 1 0 1 2.2361 1.4142 1 1.4142

3 2 1 0 3.1623 2.2361 1.4142 1

1 1.4142 2.2361 3.1623 0 1 2 3

1.4142 1 1.4142 2.2361 1 0 1 2

2.2361 1.4142 1 1.4142 2 1 0 1

3.1623 2.2361 1.4142 1 3 2 1 0

The columns and row numbers refer to the row in your XY list. So for example, the element at Row 2, Column 3 of distances corresponds to the distance between point (row) 2 of your XY, and point (row) 3 of your XY. So you'd want to look at the diagonal one above the main upper left-to-lower right diagonal. You'll see it is the same list of numbers as consecutiveDistances.

Best Answer

Related Solutions

MATLAB: Find the Euclidean distance

MATLAB: Distance between one point and the next of a list of points

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