how to get x and y values from a graph ??

[shan2036]

I have a graph between irradiance and time for 24 hrs and I want to sample and get irradiance value every ten minute.please help.

[AHK]

Hello Shan,

Use the property node Value of the graph thro which you read the values.

[shan2036]

hi,

Thanks for ur reply.

can you please explain a bit further.I am attaching the vi .

[AHK]

 Hi Shan,

 I have LV 8.5.1 can you save the VI in 8.5.1 and can you post it again

[shan2036]

okie,

here it goes ,

WR

Shan

[shan2036]

hey AHK,

u didn`t replied to my post....

actually i want to resample the graph and use it in other vi.

br

shan

[smercurio_fc]

Do you have a fixed sample rate? If it is you would just need to peel of every Nth element of the array which corresponds to 10 minutes. Can you provide an example of your data? What do you want the output of the VI to be?

[shan2036]

hi,

I used data from rows thirty to last to plotting graph,whose vi I have already attached. The graph is more like inverted parabola.Now I want to sample it for every ten minutes and use the irradiance value in another vi. Hope u will reply fast .

[smercurio_fc]

I don't understand what the numbers mean. With the first set of numbers it seems that the first column refers to hours, ranging from 0 to 24. For the second set of numbers, the range is 8.1833 to 16.6667. Are these also hours? Are you looking for an interpolated value?

Also, as far as reading the data: are you supposed to select a specific curve to read?

[shan2036]

actually it also represents irradiance but as there is no sun before 8 so its zero and started from 8.if you input the file in the vi and run you will get an inverted parabola graph. Now I like to sample this graph for every ten min.