Use of shift register and similiar C code

[vasu]

Hello LabVIEW Gurus,

I am very new to LabVIEW and I did searched the forum for my short question but the answers were not that clear to me. My question is what is a shift register and could you please give me one similiar C code and where shift register can be used.

Thanks for your time.
Vasu

[falkpl]

there is no direct analogous to a c construct to a labview shift register but a shift register is an unnamed temporary variable for use with itterative loop structures (for and while).  See the following code

int sum = 0;

for(i=0; i>100: i++)

{

sum = sum  + i;

}

return sum;

This can be done in LV without naming the variable sum .  In addition the shift register can be initialized or not.  If you do not register the shift register it will remember the value from call to call (a very cool feature when you learn to utilize it). See below

Paul

[vasu]

Thanks for the reply. Is shift register like static variable?

[Ben]

It been along time since I've C'd but I believe the analog was called a "Static Local".

It is available only inside the function and its value persist from call to call.

Ben

[falkpl]

Good call on the static local.  I forgot to mention that the shift register belongs to the vi (this is why it retains its value from run to run within an application).  It is sometimes hard to map c to labview since c is a procedural language (c++ is object oriented) but labview is a data flow model.

Paul

[Luo_Yi]

Yes, you right. Labview Shift-Register is just like static variable in C code. It's a wonder feature in labview.