Problem with linear chart

[Qooler]

Hello.

After two days tray to solve problem, I need your help.

I have problem with presentation some data. Data growning aproxx. linear. I read this data from device. Sometime my .vi not successful read data and in this case my chart have sags to zero (see on picture)

http://prntscr.com/6yq9y2

How I can make chart :  if not succesfull read data use previous value to show on the graph? In this case I not have big sags to zero.

Pls help.

[GerdW]

Hi Qooler,

easy solution: when you don't want those zeros in your chart you shouldn't put them into the chart plot!

if not succesfull read data use previous value to show on the graph?

Some pseudocode:

new value := readDAQ()
IF error on reading new data THEN
  new value := old value
ENDIF
plot(new value)
old value := new value

Please attach images/VIs/files directly in the forum using the attachment button right below the message edit box. Using 3rd party websites will just lead to problems when accessing this website from behind (company) firewalls!

[mikeporter · Accepted solution]

Another option would be to replace the 0 with NaN, this would produce a gap in the display that would communicate that a data point was missing.

Mike...

[Qooler]

Mike,

How I can use NaN for this simple graph. Thee random numeric plot to graph. If random number 0 use NaN? (this is same case like my problem when read data from device)

http://prntscr.com/6z1n74

[GerdW · Accepted solution]

Hi Qooler,

again: PLEASE DO NOT POST LINKS TO 3RD PARTY WEBSITES! Attach images directly in this forum!

Yours: (Using AutoClenaup would be nice before posting images…)

Mine:

[mikeporter]

The question is why the 0 is happening in the first place. The preferred method would be to detect that cause and use it to trigger the substitution .

Mike...