Math Is Fun Forum

pari_alf

Member

Registered: 2013-12-01

Posts: 85

resamling the points

how can we get the equal interval points along the line direction?>
Which resampling method would be better to use .

Thanks

Bob

Administrator

Registered: 2010-06-20

Posts: 10,643

Re: resamling the points

hi pari_alf

I'm just going to make a diagram to go with this.  So if you can, stay on-line.

Bob

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Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

Bob

Administrator

Registered: 2010-06-20

Posts: 10,643

Re: resamling the points

Have a look at my graph below.  You click on it to get it normal size.

Do you want to be able to divide AB into a set of equal segments, each with its own coordinates ?

Bob

---

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

pari_alf

Member

Registered: 2013-12-01

Posts: 85

Re: resamling the points

yes right..

Bob

Administrator

Registered: 2010-06-20

Posts: 10,643

Re: resamling the points

OK.  I've changed the graph a little to make an easier example.

Let's say A is (2,3) and B is (12,8), and we want to divide the line into 5 equal parts.

(12-2)/5 = 2 and (8-3)/5 = 1   so we can step from point to point by going across 2 and up 1.

The points are (2,3) (4,4) (6,5) (8,6) (10,7) and (12,8)

So now to generalise that into a formula.  For the x coordinates :

where i goes from 0 to n

and the y coordinate is similar.

Bob

---

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob