How to count the number of point and know their coordinates in a specified area from a scatter plot

Hi all,

So, how to o count the number of point and know their coordinates in the specified area (the red area) from the scatter plot? I imported my array from excel, and this is my code below so far....

clf

clear all

clc

load ax

load ay

scatter(ax,ay);

xlabel('xlabel');

ylabel('ylabel');

Answer 1

[Stijn Haenen]

Hi,

This can be done with:

bx=ax(abs(ay-1.5)<0.2); by=ay(abs(ay-1.5)<0.2);

num_b=numel(bx);

[ka chun yick]

Hi,

Can you further explain "bx=ax(abs(ay-1.5)<0.2); by=ay(abs(ay-1.5)<0.2)"

[ka chun yick]

Thank you

Answer 2

[Stijn Haenen]

Sure,

Lets start with a simple example:

x=1:10;

If you want to make an array with all the vallues of x that are for example larger than 5 you can use:

array=x(x>5); --> array = 6,7,8,9,10.

In your example you want all the point that with a y-coordinate between 1.3 and 1.7, in other words around 1.5 +-0.2.

Translating this to my simple example with x=1:10 where the output should be for example between 4 and 8 requires:

output=x(abs(x-6)<=2);