Nested For loops and Waveform Charts

[SercoSteveB]

Assuming that before execution the display of each was clear; which of the following Waveform Charts is displaying the data generated by the VI?

a)

b)

c)

d)

[mini09]

I hope none maches my result... 90% of my result is C. explain ur concepts too....

[w0utje]

don't know, I don't see the pictures

[SercoSteveB]

Apologies, was having trouble posting at work so tried at home.  Everything looks ok now?   Just realised I didn't make a note of the original order of the answers, be aware these may have changed!

[mini09]

The ans is C steve....

[RustyStrings]

I thought the answer was C but then ran the code, now I say the answer is A

(these things are not intuitive)

[mini09]

Yeah Rusty you are correct i made a mistake by interchanging the N terminal values. the answer is A

[SercoSteveB]

Answer A:

It seems OK to me.  If I were to remove the inner loop and run the VI; I would get a 1D array (a single column) and a single plot of five points on the chart.  If I add an additional loop (so its like as shown in the question), I would expect it to add a column to my (now 2D) array for each iteration.  These additional columns should translate to additional plots of the Waveform Chart.

Some info on the data you can write to graphs and charts - from NI.com

[SC_8]

ans d

[RAMESHB]

ans D

[crossrulz]

Rameshb, did you not read where Steve told you the answer is A?  Furthermore, did you try to run the code?

And on a final note, you know that the answer will have to do with 3 and 5 (the number of times the FOR loops are ran.  So is it 3 waveforms of 5 elements or 5 waveforms of 3 elements? That logic brings it down to A or C.

[erganesh]

Answer A

[ashwinilele]

Ans is A .

I think that 3 plots 5 points . Because in waveform chart by default transpose array is ON.

While in waveform Graph it will be 5 plots and 3 points ...

Is this correct?

[ra123]

ANS is D.

it is plotting of 3 colums as individual plots.

[RustyStrings]

Why do you think it only plots 3 times in the x scale?

Read what SercoSteveB has written above

Another way to think about it is:

There is an inner loop that will creat an array with the values

0,1,2

this loop is run 5 times and a 2d array is created, and plotted

The data will be:

[0,1,2],[0,1,2],[0,1,2],[0,1,2],[0,1,2]

try writting the code to see what you get

if the plot was fomatted like this it may be easier to see

[RustyStrings]

I think the confusing thing is that the data that is in a column of an array is plotted on the x axis of the graph

[xh218]

By default, the waveform chart treats each column in the array as a single plot. Wire a 2D array data type to the chart, right-click the chart, and select Transpose Array from the shortcut menu to treat each row in the array as a single plot.

--From LabVIEW help file.

[ersmt444]

By reading comments,Question will be very interesting but i am not able to see the image.Image is broken.

[Blake.N]

Ans A

[skian]

A