02-23-2009 01:33 PM
Hello,
-I would like to add a timestamp to each logged value using low-level file VIs' (see the attached example). How is this done?
-How do I add new columns/input channels of data? Is it possible to add labels to these columns?
-Regarding the Build Array item in the example, how often does it output a 1-D array if it is in an infinite While loop?
What are the advantages of using low-level VI's rather than the Express VI's (our application is simple now, but likely to get more complicated)?
Thank you
MCU
02-23-2009 01:44 PM
02-23-2009 01:45 PM

Though I wouldn't call this a Low-Level File VI because it has nothing to do with File VI's.
02-23-2009 01:47 PM
Hi MCU,
"Regarding the Build Array item in the example, how often does it output a 1-D array if it is in an infinite While loop?"
Well, if all answers are as easy as this one ![]()
I would suggest to go through these lessons:
02-23-2009 01:50 PM
02-23-2009 03:31 PM - edited 02-23-2009 03:37 PM
Hello,
>Ravens Fan
>
>Though I wouldn't call this a Low-Level File VI because it has nothing to do with File VI's
How do I add this as a timestamp column to the spreadsheet (next to the Random Number column)?
>GerdW
>Hi MCU,
>"Regarding the Build Array item in the example, how often does it output a 1-D array if it is in an infinite While loop?"
>Well, if all answers are as easy as this one ![]()
>I would suggest to go through these lessons:
I have been through a couple of lessons. Is there one in particular that you can recommend? Thanks.
>Dennis Knutson
>Here's another way.
Where is the VI that the Date/Time string feeds into found?
What situations would you recommend use of low-level File IO compared to Express VI's?
Thanks
02-23-2009 03:43 PM
MCU wrote:Hello,
How do I add this as a timestamp column to the spreadsheet (next to the Random Number column)?
You just need to build it into the array along with the random number generator.
Where is the VI that the Date/Time string feeds into found?
It is on the timing palette.
What situations would you recommend use of low-level File IO compared to Express VI's?
Express VI's if you want to get something up and running quickly, or your not sure how to do it. You can even do a right click and Open Front Panel on an Express VI to see the underlying code.
Otherwise, use the lower level File IO so you can have better control over how they work.
Thanks
02-23-2009 03:47 PM
MCU wrote:Hello,
>Dennis Knutson
>Here's another way.
Where is the VI that the Date/Time string feeds into found?
It's in the same place as when you used it in your first example. It's the Build Array.
The higher level file I/O functions such as Write to Spreadsheet file, Write to Measurement File, etc., open and close the file each time they are called. this adds additional overhead and makes the file writes slower.
02-23-2009 03:50 PM
Dennis Knutson wrote:
MCU wrote:Hello,
>Dennis Knutson
>Here's another way.
Where is the VI that the Date/Time string feeds into found?
It's in the same place as when you used it in your first example. It's the Build Array.
The higher level file I/O functions such as Write to Spreadsheet file, Write to Measurement File, etc., open and close the file each time they are called. this adds additional overhead and makes the file writes slower.
Yes. When I first read the question, I thought they were asking for the location for the Date/Time String function.