Transposing data in an array using a For Loop

I am trying to transpose some data in an array using a for loop starting from the size of the array then decrement down to 0. Can someone please help if you have an example?
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I feel as if reverse 1D array may help
Edit: misunderstood what your second post meant.
CLA, LabVIEW Versions 2010-2013

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Weird problem with loading data from an XML using a for loop

Hi,
I have a strange problem. I have encountered this thing many a times but still don't know the proper workaround for it.
I am trying to load swf file, a video file or an image. They can be present on a local system or on a remote server also. All the entries corresponding to the files to be loaded is made in an XML file. I traverse through the nodes of the XML using a for loop. On the complete event of loader info, example:.
loader.contentLoaderInfo.addEventListener(Event.COMPLETE, onComplete);
I fill a container with the loaded data.
My problem is when I am using for loop it doesn't works properly but if i use a statement like this:
someFunc()
     if(i<arr.length())
     ... do something...
     loader.contentLoaderInfo.addEventListener(Event.COMPLETE, onComplete);
private function onComplete(e:Event):void
... do something...
i++;
All files are loaded properly.
I think this can be because the for loop processes pretty fast but the content takes time to load, which ultimately leads to some wierd results.
Please let me know how can this thing be done correctly by using a for loop also.

You don't want to use a for loop to load several items. The way you almost appear to have it is the proper approach... load a file and use the completion of its loading to trigger loading the next file.

I'm creating an array using a for loop, how do I get the values outside the loop while it is running? thanks

I'm creating a set of values using a for loop and a shift register inside the loop. I want access to these values outside the loop as they are being created inside. When I connect a wire from the shift register to a display outside, it doesn't work. How do I do this? Thank you.
Attachments:
tamko_new.vi ‏29 KB

I tried to create the local variable that was wired to numeric indicator inside the loop. If I try to connect this to the analog output outside the loop, the loop just starts blinking and nothing happens, am I doing something wrong? Thanks again.
Attachments:
tamko_new2.vi ‏29 KB

Problem cycling through elements of an array using a for loop ~ error 200609?

Hi,
I'm outputting a 194-element array from a MATLAB script node into a for loop where the array is indexed then converted into a 8-bit boolean pattern which I'm trying to output using DAQ Assistant. I'm using LabVIEW 8.2 and a PCI 6133 DAQ using a counter(Ctr0InternalOutput) to time the output. The first element of the array goes through the loop perfectly however never makes it's way back through and throws error 200609: Generation cannot be started because the slescted buffer size is too small. Increase the buffer size. After probing the line before DAQ Assistant I confirmed only one element makes it through the loop and then throws this error? I've trying doing the same things with lower lowel DAQmx vi's using a DAQmx configure output buffer vi to override this buffer size problem, but still get the same result(not the error but same data flow problem)? Anybody know what's going on? I've included the vi's I've been working with. Thanks!
Millie
Attachments:
Untitled 22.vi ‏228 KB
Untitled 34.vi ‏180 KB

Hi,
I'm outputting a 194-element array from a MATLAB script node into a for loop where the array is indexed then converted into a 8-bit boolean pattern which I'm trying to output using DAQ Assistant. I'm using LabVIEW 8.2 and a PCI 6133 DAQ using a counter(Ctr0InternalOutput) to time the output. The first element of the array goes through the loop perfectly however never makes it's way back through and throws error 200609: Generation cannot be started because the slescted buffer size is too small. Increase the buffer size. After probing the line before DAQ Assistant I confirmed only one element makes it through the loop and then throws this error? I've trying doing the same things with lower lowel DAQmx vi's using a DAQmx configure output buffer vi to override this buffer size problem, but still get the same result(not the error but same data flow problem)? Anybody know what's going on? I've included the vi's I've been working with. Thanks!
Millie
Attachments:
Untitled 22.vi ‏228 KB
Untitled 34.vi ‏180 KB

Iterating through every other (or specified number) of element in an array using a for loop

I am trying to go through an array but instead of autoindexing I want to skip every other element or maybe a number of elements that will be specified for the user.
Basic functionality that I want to acheive is the following in C code.
int temp_var = 10;
int i=0;
for(i=0; i<=1000; i=i+temp_var)
I am very new to LabVIEW and I did not know how to use internal variables.
Can this be acheived using shift registers?
I am attaching the code I currently have for this. Let me know what you think.
Thanks guys.
Solved!
Go to Solution.
Attachments:
24_Sep_NchanNSamp.vi ‏44 KB

tbob wrote:
I have been asking for a new For Loop style that would allow us to specify start, stop, and step conditions, but it seems that many people are just not for this idea. Don't know why?
See here.
I wouldn't say there aren't many people for it. The idea you linked to was one of a half dozen of basically duplicate ideas, including another one of your own.
These two ideas have a fairly large number of kudoes showing people want the idea.
Smart Iterators with Loops
For Loop Increment

Using a For Loop Index for Array Element Number?

Hi. Thanks in advance for the help. I can't seem to find what I want to do here using the search function... probably because I don't know how to frame the question appropriately. Ignore the title to this post cause it's probably wrong vocabulary for what I want to do.
Here's the situation:
I have a 2D array where the first column is the X data and each subsequent column is Y data (call it Y1...Yn). The n-value varies from run to run (some runs have 4 columns of data, some have 20), but that is easily gathered when reading the data file. I need to perform a number of operations on each set of data, the least of which is smoothing the data and graphing it, so I'm limiting my discussion to these 2 operations.
What I want is a for loop structure where the indexing of the loop tracks the Y1...Yn columns, grabs each column for the iteration, performs the relevant analysis, and spits out the result, but in a stackable manner. Thus the title; I want to use the for loop's index to mark the array element for building a new array.
See the image attached. A 2D array of 9 columns (X, Y1...Y8) is analyzed such that each data set, (X, Y1), (X, Y2)...(X, Y8) is bundled, graphed, run through a B-spline Fit, of which is also graphed. I need to replace this with something that looks like the for loop structure shown.
I just don't know how to get those two data bundles [(X, Yi) and it's smoothed pair] out of the for loop in a stacked set from every iteration of the for loop.
Again the title, I think I want to build a new array where i use the index of the for loop to control the entries of the new array. But I can't see how to do that.
Any help would be appreciated.
Attachments:
NeedForLoopForThis.PNG ‏30 KB

Hello H.R. Dunham, and welcome to the forum!
It seems that you may be looking for Auto-Indexing, a basic feature of loops in LabVIEW. You'll need to transpose your array before wiring it into the for loop, as elements are auto-indexed by row before column, but at that point you should be able to operate on each column and output an array of n cluster elements corresponding to your input columns. Auto-indexing tunnels look like brackets to indicate each element will be indexed automatically- this should be the default when wiring an array into a for loop or when wiring anything out of a for loop.
As for how to build your pairs, I suggest removing the X column and creating a "starter" cluster containing your X data and placeholder Y data before entering your "Y" processing loop. Use the bundle by name function in the for loop to insert your processed column data into the cluster and auto-index the cluster output. Flow would be something like this:
1) Gather data
2) Split X and Y using standard array operations
3) Create "template" cluster with shared X data
4) Pass template cluster and Y-column array into an auto-indexed for loop.
5) Insert processed Y data into cluster inside loop.
6) Auto-index cluster data out of loop.
This tutorial is probably also a good place to get started:
Getting Started with NI LabVIEW Module 3: Loops
http://www.ni.com/white-paper/7528/en/
Hope that helps!
Regards,
Tom L.

Using a For loop to call one array element at a time

I have been working on a VI that reads a GPS unit, parses the data, outputs what I need, compares the actual GPS location to the desired location, determines a desired heading and moves on from there. My question pertains to the number of desired locations I can input right now. I need to be able to input a predtermined number of locations (not just the one that I can input right now). I was told that it is possible to use a For Loop with an array and have the first set of Lat and Long values run through the VI and when everything is complete that the next set of values will be chosen. Does this mean that I need to put the entire VI inside a For Loop and have the array update as soon as the VI has completed its first mission? I understand the concept of how this work from other programming languages but I'm not sure how to implement the solution in LabVIEW. Any help would be appreciated.
Adam

adamoutlaw wrote:
Here is a portion of the VI. I need two separate arrays, one for Latitude and one for Longitude, of the same size.
I don't see any arrays in your code. Do you want to generate arrays form individual data points or do you want to process arrays, one element at a time? Both can take advantage of autoindexing. Here's a simple picture.
Your VI contains a weird mix of DBL and EXT precision. Most likely all you need is DBL. Keep your representations consistent!
Message Edited by altenbach on 08-02-2007 07:14 AM
LabVIEW Champion . Do more with less code and in less time .
Attachments:
Indexing.png ‏4 KB

Row operation on array with a For Loop

Hi,
I'm working with a large one dimensional column array. I'm trying to do the following
for i=1:size(A)/2
B(i,: ) =A(1+(i-1)*2:i*2)
So, for example if
A=
0
1
2
3
4
5
6
7
then
B=
0 1
2 3
4 5
6 7
My approach was to use an array subset block inside the for loop to select a number of elements but I'm not sure how to transpose the selected elements into a new row to create the new array B. Is there a more straightforward approach?
Thanks,
Mike
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try experimenting with the reshape array feeding it your input array and re-sizing it to output a 2d aray. It is much faster than using a For loop becuase the data never gets moved and LV just changes the array dimensions and updates the stride.
Ben
Ben Rayner
I am currently active on.. MainStream Preppers
Rayner's Ridge is under construction

Creating an array in a 'for' loop (resetting loop count)

Hi,
I am trying to integrate an acceleration signal coming from a CRIO analogue input to obtain the speed and then further integrate to get the displacement of a vibration system.
I understand that in order to perform the integration, an array has to be fed in. My problem is that I could not buffer the signal in a buffer block as I couldn't find any buffer blocks. so I decided to create my an array of data using a 'for' loop. The 'for' loop nests inside a timed loop. The problem that I got stuck at is how to reset the 'for' loop in order to refill the buffer again at every iteration of the outer timed loop.
I have attached the code if that helps. Note that I am using labview 2013.
I would be gratefull if someone who had encountered a similar issue before can help me.
Regards
Ali
Solved!
Go to Solution.
Attachments:
acc_test.vi ‏42 KB

Dear Altenbach,
Many thanks for your reply.
I need to make it clear that I have not had enough hands-on with labview, I have only used it for sometime in the past and now I have to in order to perform some active damping on a 50Hz running machine. I must stress the fact that what i find more intuitive to do in a different programming language (matlab or C) is not as straightforward in labview. so please bear with me if my code has basic mistakes .
All what i am trying to do is obtain the speed and position from an acclerometer signal. unfortunately i dont have a position sensor so i have to measure acceleration then perform time integrations in order to obtain the speed and position respectively. I am using a compact Rio (later in FPGA mode) to take physical measurements of acceleration from the vibratory machine and where i managed to do this bit successfully. when it came to performing the integration, i had to create an array inside my timed loop since i couldn't find a buffer block. I implemented a 'for' loop inside a timed loop in order to build the array. however i got stuck at resetting the count of the 'for' loop in order to refill the array with new values at every new iteration of the outer timed loop. unfortunately, even a sensible answer has been suggested before, i dont seem to have been capable of doing it yet. I really spent all my day trying to figure a way out but not achieved it yet, nevertheless I have learnt many many things by playing around.
I would be gratefull if you could comment on a possible way of doing what i am trying to do.
Kind Regards
Ali

Truncating an array within a for loop

I'm currently working with a program that builds an array of 3000*N real numbers, where N is a control that I specify. I want to pass this array into a for loop that runs N times, each time splitting the first 3000 numbers of the array. So, in other words I want the for loop to execute enough times such that the initial array will be completely divided into groups of 3000 when I'm finished. Later I'll be finding the maximum value of all of these subarrays and taking the average of those. What I tried first is to pass the array into the for loop, then truncate it at index = 3000, but the problem is that I can't hard code the loop to do this N times. Any advice or other methods you'd recommend for doing this?
Thanks.
Message Edited by Robtn on 03-05-2010 03:17 PM

Mark--I don't think I can use that approach. Let me be more specific on what the problem is:
Our "big program" is a giant while loop that constantly reads in voltage values from a DAQ assistant.
It has two modes, the first of which I'm having a lot of trouble with. This mode uses a for loop (N = 3000) nested within the giant while loop.
When the for loop activates, the DAQ assistant takes reads 300 samples for every iteration and takes the maximum of those 300 values. It then builds an array composed of all the maxima. After the for loop has executed 3000 times, a case structure activates, which then finds the maximum of the array of maxima.
I want this (N=3000) for loop to execute an arbitrary number of times, a number that I will specify. Each of those times it should generate a completely seperate array of maxima. So, if I want the for loop to run 5 times, I want 5 different arrays.
My approach for doing this was to change N=3000 to say N = 15000, then split up the resulting array 5 times. So, I need an entirely separate for loop that reads in this array of 15000 maxima on its own and splits it 5 ways. I think what you're suggesting is to use a for loop outside of the N=3000 loop, which is a good idea in theory, but experience has shown that this will not generate 5 separate arrays. It will actually concatenate each array into one, hence the problem we currently have.
Yik--I won't have access to Labview over the weekend. Is it possible to take a screenshot and post it, or maybe a short description?
Thank you for the responses.

I have used a 'for loop' to create an array of output data, however I want the each of the data sets from the array to be placed into a 1-D array. How do I concatenate the output of the for loop into a 1-D array?

I am using this to create a data set that will be passed as an anolog output therefore it needs to have the correct array dimensions to go into the analog write vi.

I'm updating my request... I've figured out how to do this by copying an example that uses a simple FOR loop (as seen in the attached current version of my VI). My question now becomes this: Is there a way to save the Y values corresponding to those X values into two more arrays? That is, just for argument's sake, let's say I took the first 100 elements from the X array, and found them to be positive. Then I would like to take the first 100 elements of the Y array and put them into a 'Y Values for X > 0' array. ...And likewise with the negative X values, they should have a separate array of corresponding 'Y values for X < 0' array.
I can see that I should somehow save the indices of the positive X values from the large arrray wh
en I sort them out, and use those indices to pick out the elements from the main Y array with the same indices.
I just can't seem to set up the code necessary to do this. ...Can anyone help, please?
Attachments:
Poling_Data_Reader_5i.vi ‏79 KB
30BLEND.txt ‏3 KB

Why are date and time strings lost when indexing an array in a for loop

Hi,
I have an application where i'm reformatting data from a spreadsheet for graphical display on a LabVIEW dashboard.
the original spreadsheet has date and time values in separate columns, and i'm merging them and converting to a timestamp value. But something's not working. Does anyone know why the string value is lost when the array indexes into this for loop?
Attachments:
failed array index.png ‏142 KB

Can you attach your VI with some typical values? (e.g. create in indicator on the 2D array, run your VI, then turn the indicator (now containing data) into a diagram constant). Place the FOR loop related code and that diagram constant into a new VI and attach it here.
How many times does the FOR loop run? Could it be that the last element of each 1D array is an empty string? (unless you put a wait inside the FOR loop, you'll never see the other elements in the probe)
LabVIEW Champion . Do more with less code and in less time .

I want to open a txt file and output data through an AO-using DAQmx for PXI

I have a PXI running a 8145RT CPU. I have a PX6040E Multifunction DAQ card installed in the PXI. I want to program an application where I open a txt file (existing in one of the the RT machines' folders), read the first row, and output its data through an AO channel. The drivers I should use is DAQmx v7.1, and the Labview RT v.7
Any idea?

What exactly are you having problems with? Reading a text file can be done a number of ways. Look at the File I/O palette and check out Read Lines From File or Read Characters From File. There are string to number conversion functions on the string palette (i.e. Scan From String). There are also numberous shipping examples on using DAQmx for analog out. If you have a specific problem or question, please post back with additional details.

How to revert the data that is loaded using BDC for transaction PA30

Hi All,
We had loaded the data in SAP using BDC-Session Unfortunately.
Now we want to delete all the data which is loaded usong these sessions.
Please can anyone know the procedure to do so.(May be using LSMW)
This is the test environment.
This is the HR Data.
Transaction we used is PA30.
Thank you,
Edited by: Kumar B on Sep 16, 2009 6:55 PM

Sorry All for the late response.
Thanks Swathi ..I thought in same manner.
But we used the LSMW,It deleted the records in the exact fashion we need.
It was a nice experience.
Use T-code SE38 run the report RPUDELPN and pass the pernr entire data will delete. as it is a test client then go to NUMKR Feature reset it and upload the correct data again.
I think that would not have worked for us as it deletes all the employee records.
Might be dangerous too
If it is has standard fast entry screen then use pa70 for mass deletion
Apart from deletion,Also we need to delimit the previous record.
Thank you All

Passing an array in a for loop to a procedure

I am trying to pass an array in a cursor for loop to a procedure which performs a table insert using the array's contents. Somehow I am missing something, or it is not possible. The compile error states: PLS-00306: wrong number or types in call to 'insert_address' I checked to be sure I am creating the arrays in both cases from similar data objects. Both address and work_address_table contain the same 4 columns with the same data types.
create or replace package work_address as
FUNCTION populate_address return boolean;
procedure insert_address(in_address IN work_address_table%ROWTYPE);
end work_address;
create or replace package body work_address as
function populate_address return boolean is
cursor c1 is
select 'H' as header,
street1 as street
city as city,
NULL as state
from address
where city = 'HANOVER';
TYPE addressT IS TABLE OF c1%ROWTYPE INDEX BY BINARY_INTEGER;
rec1 addressT;
BEGIN
OPEN c1;
FETCH c1 BULK COLLECT INTO rec1 LIMIT 500;
FOR i IN 1..rec1.count LOOP
rec1(i).state := 'US'
insert_address(rec1(i));
exit when c1%notfound;
END LOOP;
CLOSE c1;
return TRUE;
END populate_address;
PROCEDURE insert_address(in_address IN work_address_table%ROWTYPE) IS
BEGIN
INSERT INTO work_address_table
VALUES (in_address.header,
in_address.street,
in_address.city,
in_address.state);
COMMIT;
END insert_address;
END work address;
/

Both address and work_address_table contain the same 4 columns with the same data types.Are you 100% sure about this?
SQL> declare
cursor c1
is
    select 1 deptno, dummy dname, 'Loc' location from dual;
type addresst is table of c1%rowtype
    index by binary_integer;
rec1   addresst;
procedure p (d dept%rowtype)
as
begin
    dbms_output.put_line(d.dname);
end p;
begin
rec1 (1).dname := 'z';
p (rec1 (1));
end;
z
PL/SQL procedure successfully completed.but changing just the first column of the cursor:
SQL> declare
cursor c1
is
    select 'xy' deptno, dummy dname, 'Loc' location from dual;
type addresst is table of c1%rowtype
    index by binary_integer;
rec1   addresst;
procedure p (d dept%rowtype)
as
begin
    dbms_output.put_line(d.dname);
end p;
begin
rec1 (1).dname := 'z';
p (rec1 (1));
end;
Error at line 3
ORA-06550: line 20, column 3:
PLS-00306: wrong number or types of arguments in call to 'P'
ORA-06550: line 20, column 3:
PL/SQL: Statement ignored

Transposing data in an array using a For Loop

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