# Gap correction between two curves

I have two curves like this :

I would like to be able to calculate the gap between these two curves according to the Y value.

For example:

• In my example Y < 5, error between the two curves is almost 0%
• But for Y=7 blue is 5% greater
• For Y=10 blue is 15% greater
• etc.

Is it possible ?

Thanks

• $(y_1-y_2)^2$.... no? – Brethlosze Jun 9 '17 at 22:24
• This is the formula to measure distance between the two Y, right? – Stéphane Jun 10 '17 at 7:11
• Oh yes, there are hundreds of ways to measure how two functions are close one each other. If you make $\frac 1 n \sum_i (y_1_i-y_2_i)^2$ you are evaluating how separated are those. – Brethlosze Jun 10 '17 at 10:43
• A percentage will be bad because it turns infinity for values oscilating close to zero. – Brethlosze Jun 10 '17 at 10:44