Calculate area under XY graph

[MSD100]

Hello to all, I am plotting the data acquired from the system as amplitude v/s time on XY graph. My task is to calculate are under the graph and am using integrator tool to achieve this. However, feel that am not using correctly as answer is not matching with expected value. For example, I have plotted y=x function and as per the definition area is equal to 0.5*height*base for area under the graph. It is not matching, kindly help as I want to find out area under the curve for any two points of X-axis.

[ejkaiser]

The integration gets accurate in your case if you change the integration method to 'trapezoidal' instead of the default 'Simpson's Rule'.

Simpson's Rule probably doesnt work because you don't provide suitable Initial and Final conditions. This method needs an assumption about the borders of the integration interval.

Cheers

Edgar

[MSD100]

yes, you are right.Now need to find area between two particular X-axis points.

Thanks a lot. 

[MSD100]

Is there any way to calculate if dt is not fixed??? 

[DFGray]

Yes.  Use the Uneven Numeric Integration VI.