data logging every 0.5 voltage.

[Amit Patel2]

Hello,

I'm new to Labview.  I am trying to create aVI that would log data into excel file every 0.5v voltage drop.  Fox example, in my VI code every time my BEAM voltage drops from 1.0v to 0.95v, 0.95v to 0.90v, 0.90v to 0.85v so on; i want my VI to log my BEAM reading and MIC reading. it doesn't matter what MIC value is at time of voltage drop.  Please help.  I've attached my rough VI.

[GerdW]

Hi Amit,

never, never ever, under no circumstences compare floating point numbers for equality!

Now you should define that "voltage drop" more detailed (maybe voltage drop in a certain time) as now you just compare current value with last reading...

[smercurio_fc]

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@GerdW wrote:

Hi Amit,

never, never ever, under no circumstences compare floating point numbers for equality!

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And if you do, first you give me another nickel in my retirement fund. Then go read this: http://www.parashift.com/c++-faq-lite/newbie.html#faq-29.17

[Amit Patel2]

i am comparing current value vs last value.  I don't care about timing.

Thank you for your help

Amit

[Amit Patel2]

Hello there,

my signal has too much noise or oscillations.  I want to take the a average every second or so and if the average value is less than 0.005 from the previous average value then i want to logg it.  Can anyone please give me an idea?  Thank you for your help.

Amit

[GerdW]

Hi Amit,

there are several functions in the Math palette to calc the mean - choose one of them...

[Kevin_F]

Hey Amit,

This example shows how to calculate a running average of an array which is similar to what you are looking to do:http://zone.ni.com/devzone/cda/epd/p/id/5229 You will need to modify this implementation in such a way that you can keep track of differences between the previous average and your average over the last second but the overall concept should be similar.  Please post back if you have any additional questions.