# how to arrange x-coordinate w.r.t y-coordinates?

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Ammy on 23 May 2021
Commented: Ammy on 23 May 2021
I have a pair of coordinates (x,y) , I arranged it in increasing order of y by using
sortrows(A,2) % A is matrix with first column as x-coordinate and 2nd column as y-coordinates.
I have
(4,0)
(10,1)
(7,2)
(6,3)
(9,4)
(1,5)
(1,6)
(9,7)
(6,8)
(7,9)
(10,10)
But now I want to arrange the x-coordinates if y-coordinate is given like I want to arrange x ,w.r.t y-coordinate [ 0 7 7 4 1 7 3 3 10 2] , In other words I want tp arrange it w.r.t to y-coordinate if y is given how to search for x ,I need the following
(4,0)
(9,7)
(9,7)
(9,7)
(10,4)
(9,7)
(6,3)
(6,3)
(10,10)
(7,2)
Ammy on 23 May 2021
Thank you.

Torsten on 23 May 2021
Something like
As = sortrows(A);
x = As(y(:)+1,1)
where y is the vector of y-coordinates ?

Kartikay Sapra on 23 May 2021
A = [1 2; 3 4; 5 6]
map = containers.Map
[row col] = size(A)
for i = 1:row
A(i,1)
map(int2str(A(i,1))) = int2str(A(i,2))
end
y = input('Enter y coordinate')
str2num(map(int2str(y)))
You can try using a map object, here, you can place y co-ordinates as keys and x co-ordinates as value. Whenever we want the corresponding x value, search value of y
Ammy on 23 May 2021
@Kartikay SapraThank you very much for your valueable comment, but my problem is solved with @Torsten answer.