graph interception

[ahmadtarmimikassim]

Good Day

which function in vi is suitable to use to know  the graph interception of coordinate 'X'  for cursor C refer to diagram attachment?

problem:  how to place the cursor to the interception point with known Y value....without insert value manually into the start index(0)

attached also my vi for reference

Best Regards

Tarmimi 

[ahmadtarmimikassim]

Good Day 

Any help or advise guys?

Best Regards

Tarmimi

[natasftw]

To place a cursor: http://digital.ni.com/public.nsf/allkb/280875F12A53D4FD8625699E006F0BBA

To answer your other question, you'll want to traverse your array of data to find the point where it changes from being less than the cursor value to greater than.

[ahmadtarmimikassim]

Good Day Natasftw

thank for your reply

How can i transverse the array data? can you give an example

best regards

Tarmimi

[natasftw]

Do a greater than/equal to the cursor value.  This should provide you with an array of booleans.  Create a loop to run through these values to see when they switch from true to false and vice versa.  Save an array of those switches as an output for your loop.  You'll have all of the interceptions.

[ahmadtarmimikassim]

 Hi natasftw

very sorry i  still not get the idea (refer attachment) due to my lack imigination in convert into labview programming .... can you help me by  giving a simple example using vi...

Bes regards

Tarmimi

[natasftw]

Very quickly thrown together example.  You can change the values in the data array.  You can change the cursor value to be whatever you'd like.  The boolean array is just for show.  You don't need it in an actual application.  This just helps you see each of the elements in the array is checked against the cursor and makes it easy for you to scan the array to see when it changes from below to at/above the cursor.  The final array is a list of all the elements where the value in the boolean array changed.

In the future, attach the code you're working with rather than a picture that shows a very limited piece of your actual work.

[ahmadtarmimikassim]

Good Day natasftw

thanks for your reply

I did attach my vi code on first posting, re attached again

I try  combine your  vi with mine but still not getting  the  value of X axis with known value of Y...

if you run  example the test measurement exponential.vi  for  cursor C i know the value of Y=0.501176 and X=30, but what i to know is the interception graph when  Y still 0.501176, and X unknown (refer interception of graph picture)

i can change the start index(0) but it seem to response to known X value

[ahmadtarmimikassim]

Good Day

Any advise on this topic?

[ahmadtarmimikassim · Accepted solution]

Good Day

I think i solve the problem, refer to attachement , solution :using the negate

you can also refer to example from http://search.ni.com/nisearch/app/main/p/bot/no/ap/tech/lang/en/pg/1/sn/catnav:ex/q/graph%20cursor/

Thank you natasftw for your kind help and advise

Best Regards

Tarmimi