Finding area under a graph using integration trapezoidal rule

[JonTeo47]

Good day

I am having trouble of finding the area under a graph using integration by trapezoidal rule. i am trying to find the energy that is being generated, under these graphs. My dt is 5 because i have logged the data around every 5 sec interval. These are some of my vi that I have created, i hope i can get some feedback on the vi. Thank You

[altenbach]

Just looking at the graph, the area looks about right (~ 50 x 85 x 5 =21250) which is close to what you get (21492.5). What else do you expect?

• You only have one column. If you transpose, you can get the 1D output to get the first column
• Use array subset to eliminate the first element (delete from array is useful if you are also interested in the first element)
• Trapezoidal is the default, no need to wire it.
• You can set the x axis multiplier to 5 to see the correct units.
• I changed the y axis so it starts at zero and filled to baseline on the graph to show the area more clearly.
• No need to show all the function labels. You can easily tell what things are by using the context help window and hover. Much less clutter!
• You also do a double-integration. What is that for?

Here's how to set the x scaling: