How to include a sample time column in my stored data file

[shivik89]

I have created a labVIEW program by combining 2 programs. I am logging my data into a file, the problem is i want also to inlcude a sample time column. How can I do that. I am attaching my Vi and a picture of what I am aiming to get in the end. Since I am new to labVIEW i have limited knowledge. Please help.

[GerdW]

Hi shivik,

just add another signal named "Time [s]" and calculate the needed values for this signal…

[shivik89]

Okay, can you give me an idea of how to do that, can you maybe add it to the VI

[GerdW]

Hi shivik,

can you give me an idea of how to do that,

Create a new array with the values you want to use as "Time" column. Basically it looks from your image above you want to have something like "sample number / sample rate"…

can you maybe add it to the VI

Your VI is already way too big, so I will not add anything to it!

[shivik89]

I have added the sample time column, bit there is still a problem. After the for loop runs the specified number of times in the while loop there is an abrupt change in the  sample time, can anyone tell me the cause of this and how to solve it?. I think the for loop needs to keep running for the number of values that will be indexed by the while loop. How can I solve this.

[GerdW]

Hi shivik,

why do you need to call another ExpressVI in this FOR loop?

Why not use simple functions like GetDateTimeInSeconds?

Or by creating a ramp:

(This is just a rough sketch. You need to adapt sample timing in the ramp and start time t0. You might also use waveforms for this task.)

[shivik89]

That woulde be an soultion, but if my gps sensor is static(not moving) i would not work. Any other options with the express VI(I know it is not an good idea) but maybe compacter

[shivik89]

I tried the above solution, but now i got an emptuy time column

[GerdW]

Hi shivik,

when you make changes to your VI(s) you should attach them again…