index of all zero values in 1D array

[sylvainDCU]

I would like to index all zero values in a 1D array. the problem is my points fluctuate around zero without reaching the zero value. So I need to do interpolation between the points.

I don't know how I can index all zero value. Can you please help me ?

regards,

Sylvain

[MikeS81]

Hi Sylvain,

it should be possible with the "Threshold 1D Array" function.

Mike

Message Edited by MikeS81 on 07-28-2009 05:30 PM

[sylvainDCU]

The problem is the VI "Threshold 1D Array" index only the first value egal to zero and doesn't index the other values in the 1D array.

Regards,

Sylvain

[Cory_K]

I would use 'In Range and Coerce'.

In my example (attached), all values between -0.1 < x < 0.1 will be considered zero.

It then outputs a 2D array of (Index, Value)

[smercurio_fc]

I would try a variation of this. You can replace the Not Equal To Zero function in that example with the In Range and Coerce.

[Coq_Rouge]

Also be careful if you are working with floating point numbers. 1E-22 (as an example) is not equal to zero but it is indeed a small number 😉 

[dan_u]

If you don't need to interpolate the index you can check for changes in the sign. See example.

Hope this helps,

Daniel

[Spectre_Dave]

To build on what smercurio_fc said here is a solution with comments.

Message Edited by VADave on 07-28-2009 11:52 AM

[sylvainDCU]

It precisly my problem, because I'm working with floating poin numbers... I think, i need to use "Threshold 1D Array". What do you think ?

[Cory_K]

Could you please show us some sample data, and tell us what you would consider a zero?