How to access single channels of multichannel acquisition?

I want to access single channels of a multichannel acquisition in the Getting Started Analog Input.vi
The purpose of this is to analyse i.e. do Min-Max or FFT on the individual channels. Can somebody help me to unbundle the data? Why does AI Read give Scaled Data while in other vi Waveform data?

Hi,
Getting Started Analog Input.vi uses AIRead.vi to read data from your hardware.
1. This is from the help about AIRead.vi:
"scaled data is a 2D array that contains analog input data in scaled data units. The data appears in columns, where each column contains the data for a single channel."
So to access the single channel you must use "Functions->Array->Index Array.vi" to get data from your 2D array. All you need is to wire your 2D array to this VI and the specified number to the "column" input node.
2. To change the Data type of array you receive from hardware you have to right-click on the AIRead.vi and choose any of 4 options (Binary Array, Scaled and Binary Arrays, Scaled Array, Waveform) from "Select Type" sub-menu.
Good luck.
Oleg Chutko.

Similar Messages

How to access single column in table?

Hi,everybody!
How to access a single column in table.
I sorted my table with standard TableSorter.
Now I need to get one column from this table to
do something with it's data.How do I get it?
Regards,
Michael

Hi Michael,
If you just want to retrieve the data, you could use the following code.
//Get the node which the table is bound to
IWDNode node = wdContext.nodeTable();
//iterate thru the elements
for(int i = 0 ; i<node.size();i++)
IWDNodeElement ne = node.getElementAt(i);
Object value = ne.getAttributeValue("<column name>");
//Here you have the data in the value variable
//and you can manipulate this now
Regards,
Sudeep

Apple Script: How to deactivate single channels of a layer?

Hi there,
can someone probably tell me how to deactivate specific channels of a layer?
Example: Photoshop file with two layers, say CMYK. I want to deactivate CMY of the first layer, so that only K can be seen.
Unfortunately I didn’t find any information in the PS scripting guide nor in the scripting reference.
Thanks for any help on this.
andy

Paul, is correct you can't even do this in the app through the GUI. You would either need to duplicate your top layer loop through the channels that you don't want selecting all and clearing then going back to the composite or you could add an adjustment layer above the top grouped and use this by toggling its visibility (this is the way I would go). Paul 'AppleScript'? you've made me smile this morning what's come over you…
Added some code from scriptlistener…
tell application "Adobe Photoshop CS2"
activate
set Doc_Ref to the current document
tell Doc_Ref
if mode = CMYK then
set current layer to layer 1
-- delay 2
do javascript "Just_Black(); function Just_Black() {function cTID(s) { return app.charIDToTypeID(s); }; function sTID(s) { return app.stringIDToTypeID(s); }; var desc01 = new ActionDescriptor(); var ref4 = new ActionReference(); ref4.putClass( cTID('AdjL') ); desc01.putReference( cTID('null'), ref4 ); var desc02 = new ActionDescriptor(); desc02.putBoolean( cTID('Grup'), true ); var desc03 = new ActionDescriptor(); var list5 = new ActionList(); var desc04 = new ActionDescriptor(); var ref5 = new ActionReference(); ref5.putEnumerated( cTID('Chnl'), cTID('Chnl'), cTID('Cyn ') ); desc04.putReference( cTID('Chnl'), ref5 ); var list6 = new ActionList(); var desc05 = new ActionDescriptor(); desc05.putDouble( cTID('Hrzn'), 0.000000 ); desc05.putDouble( cTID('Vrtc'), 255.000000 ); list6.putObject( cTID('Pnt '), desc05 ); var desc06 = new ActionDescriptor(); desc06.putDouble( cTID('Hrzn'), 255.000000 ); desc06.putDouble( cTID('Vrtc'), 255.000000 ); list6.putObject( cTID('Pnt '), desc06 ); desc04.putList( cTID('Crv '), list6 ); list5.putObject( cTID('CrvA'), desc04 ); var desc07 = new ActionDescriptor(); var ref6 = new ActionReference(); ref6.putEnumerated( cTID('Chnl'), cTID('Chnl'), cTID('Mgnt') ); desc07.putReference( cTID('Chnl'), ref6 ); var list7 = new ActionList(); var desc08 = new ActionDescriptor(); desc08.putDouble( cTID('Hrzn'), 0.000000 ); desc08.putDouble( cTID('Vrtc'), 255.000000 ); list7.putObject( cTID('Pnt '), desc08 ); var desc09 = new ActionDescriptor(); desc09.putDouble( cTID('Hrzn'), 255.000000 ); desc09.putDouble( cTID('Vrtc'), 255.000000 ); list7.putObject( cTID('Pnt '), desc09 ); desc07.putList( cTID('Crv '), list7 ); list5.putObject( cTID('CrvA'), desc07 ); var desc10 = new ActionDescriptor(); var ref7 = new ActionReference(); ref7.putEnumerated( cTID('Chnl'), cTID('Chnl'), cTID('Yllw') ); desc10.putReference( cTID('Chnl'), ref7 ); var list8 = new ActionList(); var desc11 = new ActionDescriptor(); desc11.putDouble( cTID('Hrzn'), 0.000000 ); desc11.putDouble( cTID('Vrtc'), 255.000000 ); list8.putObject( cTID('Pnt '), desc11 ); var desc12 = new ActionDescriptor();desc12.putDouble( cTID('Hrzn'), 255.000000 ); desc12.putDouble( cTID('Vrtc'), 255.000000 ); list8.putObject( cTID('Pnt '), desc12 ); desc10.putList( cTID('Crv '), list8 ); list5.putObject( cTID('CrvA'), desc10 ); desc03.putList( cTID('Adjs'), list5 ); desc02.putObject( cTID('Type'), cTID('Crvs'), desc03 ); desc01.putObject( cTID('Usng'), cTID('AdjL'), desc02 ); executeAction( cTID('Mk '), desc01, DialogModes.NO );}" show debugger on runtime error
end if
end tell
end tell

How to make single channel doubled

I have an audio track that's only in the left channel. I need to get it into both...Any suggestions?
Thanks.

http://www.bulletsandbones.com/GB/GBFAQ.html#leftspeakeronly

How to do a single channel DAQ using NI-DAQ driver software with a PCI-MIO-16XE-10 card

Hi,
I would like to find out how I could do a simple one channel Data Acquisition from a signal generator using the NI-DAQ driver software with a PCI-MIO-16XE-10 card.
I have written some test problem but even when the signal generator is turned on/off I get back some weird values.
Here is my code.
CString sFunctionName("");
double volt[OUTPUT_POINTS*2];
double out[OUTPUT_POINTS*2];
short timebase, ready, code, stopped;
unsigned short sampleInterval;
int i, status, count=0;
unsigned long update, points;
short* ai_buffer;
short output_ch_vector[16];
int local_ITERATIONS = 2;
SAFEARRAYBOUND bound[1];
double dataItem = 9.9;
long j;
long k;
double* pTheValues;
LPTSTR lpsz_ErrMsg;
// Initialise device
status = Init_DA_Brds (deviceNumber, deviceNumberCode)
Initializes the hardware and software states of a National Instruments
DAQ device to its default state and returns a numeric device code that
corresponds to the type of device initialized
Init_DA_Brds(DEVICE, &code);
// Check return code from Init_DA_Brds
Code return should be 204: PCI-MIO-16XE-10.
if (code < 0)
CString sError;
sError.Format("Code error: %d", code);
if (code == -1)
sError = sError + ": No device found";
LPTSTR lpsz = new TCHAR[sError.GetLength()+1];
_tcscpy(lpsz, sError);
AfxMessageBox(lpsz);
delete lpsz;
return S_FALSE;
// Allocate memory for analog output and input arrays
//ao_buffer = new short[OUTPUT_POINTS*2];
ai_buffer = new short[OUTPUT_POINTS];
// Set double-buffering
status = DAQ_DB_Config (deviceNumber, DBmode)
Enables or disables double-buffered DAQ operations.
status = DAQ_DB_Config(DEVICE, 1);
if (status < 0 )
sFunctionName = "DAQ_DB_Config";
goto TidyUp;
// Get the rate parameters
status = DAQ_Rate (rate, units, timebase, sampleInterval)
Converts a DAQ rate into the timebase and sample-interval
values needed to produce the rate you want.
status = DAQ_Rate(RATE, 0, &timebase, &sampleInterval);
if (status < 0 )
sFunctionName = "DAQ_Rate";
goto TidyUp;
// Setup scan
status = SCAN_Setup (deviceNumber, numChans, chanVector, gainVector)
Initializes circuitry for a scanned data acquisition operation.
Initialization includes storing a table of the channel sequence
and gain setting for each channel to be digitized
status = SCAN_Setup(DEVICE, 1, ai_channels, gain);
if (status < 0 )
sFunctionName = "SCAN_Setup";
goto TidyUp;
status = SCAN_Start (deviceNumber, buffer, count, sampTimebase,
sampInterval, scanTimebase, scanInterval)
Initiates a multiple-channel scanned data acquisition operation,
with or without interval scanning, and stores its input in an array
status = SCAN_Start(DEVICE, ai_buffer, OUTPUT_POINTS, timebase, sampleInterval, timebase, 1000);
if (status < 0 )
sFunctionName = "SCAN_Start";
goto TidyUp;
while(count < local_ITERATIONS)
// Check whether we are ready to input another half-buffer
status = DAQ_DB_HalfReady(DEVICE, &ready, &stopped);
if (status < 0 )
sFunctionName = "DAQ_DB_HalfReady";
goto TidyUp;
if (ready == 1)
status = DAQ_DB_Transfer(DEVICE, ai_buffer, &points, &stopped);
if (status < 0 )
sFunctionName = "DAQ_DB_Transfer";
goto TidyUp;
count++;
// Clear the analog input
status = DAQ_Clear (deviceNumber)
Cancels the current DAQ operation
(both single-channel and multiple-channel scanned) and reinitializes the DAQ circuitry.
status = DAQ_Clear(DEVICE);
if (status < 0 )
sFunctionName = "DAQ_Clear";
goto TidyUp;
status = SCAN_Demux (buffer, count, numChans, numMuxBrds)
Rearranges, or demultiplexes, data acquired by a SCAN operation
into row-major order, that is, each row of the array holding the
data corresponds to a scanned channel
status = SCAN_Demux(ai_buffer, OUTPUT_POINTS * 2, 2, 0);
if (status < 0 )
sFunctionName = "SCAN_Demux";
goto TidyUp;
//Convert binary values to voltages (Doesn't actually take a reading from board)
status = DAQ_VScale (deviceNumber, chan, gain, gainAdjust, offset, count, binArray, voltArray)
Converts the values of an array of acquired binary data and the gain setting for that data
to actual input voltages measured.
status = DAQ_VScale (1, 0, 1, 1.0, 0.0, OUTPUT_POINTS , ai_buffer, volt);
if (status < 0 )
sFunctionName = "DAQ_VScale";
goto TidyUp;

Hello,
Please take a look at lots of examples available at :
1. www.ni.com >> NI Developer Zone >> Development Library >> Measurement Hardware
2. C:\program files\national instruments\ni-daq\examples\visualc
Sincerely,
Sastry V.
Applications Engineer
National Instruments

How To Access PAGE ITEM (single row) from HTML source

Hi Guys,
I have a page Item that return a string.
I would like to show this string
How To Access PAGE ITEM (single row) from HTML source?
My desire final output is
<marquee>:P1_PAGE_ITEM</marquee>
Can please help me
Thanks

Hi,
You can refer the page items in your page header as &itemname. For example, if I have page item P15_TEST, I will add the following in header:
<marquee>
&P15_TEST.
</marquee>But make sure that you have a process before header to populate the value in your page item. Otherwise, there will be a null scrolling (which you can't see!) :)
Regards,
Zahid

How do you find the average value of all the data between two points on a single channel

I am tring to calculate the average value of all the data points on a single plot between two seperate points
I have attahced an illustration.
Tim
Solved!
Go to Solution.
Attachments:
plot.jpg ‏173 KB

Hey smoothdurban,
I've seen Brad's code, and trust me, it's worth the effort to let him help you get it up and running - it's definitely the most ideal way to solve this problem. However, as Brad said, there are multiple ways to tackle this - both interactive and programmatic - so in the meantime, I'll take a second to detail one of the interactive and sure-fire ways to find the average of data between two points on a single channel.
We'll use"Flags." Set up your VIEW graph exactly as you did on your original screenshot, using Band Cursors to approximate the beginning and ending X-values representing the range you want to examine. Next:
1. Click the "Set Flags" button () that is a part of your 2D Axis System. Note that you can hold down the Shift button if you ever decide you want to do this on more than a single curve at one time.
2. Select the "Flags: Copy Data Points" button that enables after Flags are set.
3. This creates new channel(s) in the default (bold) group in the Data Portal that contains only the Flagged data.
4. Select DIAdem ANALYSIS.
5. Select Statistics » Descriptive Statistics.
6. In the Channels input, select the newly created channel containing your Flagged Y-Data.
7. Ensure that the Arithmetic Mean parameter is set. You can preview the data and the result in the dialog before pressing OK to execute the calculation.
You may have noticed that in the Descriptive Statistics calculation, one of the parameters that you can set is the range of channel rows to operate on - so, if you know the row numbers of your beginning and ending X-values, you could just simply run the Descriptive Statistics calculation and use this parameter to operate on a row subset of your original channel instead of the entire channel.
Derrick S.
Product Manager
NI DIAdem
National Instruments

Multi Channel USB Data Acquisition

I am using the following VI for arduino HC-06 bluettoth data acquisition. I would like to acquire multicahnnel data
Could you suggest me how to acquire multichannel data from USB? To do this, in what way i have to program the arduino?

Thank you very much for your suggestions. its working.
But if i give input to channel 2 or 3 or 4, they are not responding. only channel 1 is responding irrespective of input pin. what could be the reason for this?
earlier, i was acquiring single channel data at 57600 baudrate, i was getting pure sine wave signal upto 90Hz, after that it was started distorting.
Now, it started distoring above 20Hz, i think i need to increase the baudrate to 230400 to get 4 channel undistorted signal upto 100Hz,
but arduino supports upto 115200 only, what shall i do??

Continuous multi channel voltage data acquisition

Trying to use a NI 9223 to continuously sample voltage data from three channels the code work for a singel channel but when I added the other two channel I started to get errors.
I have attached my code if anyone can give me some pointer i would appreciate it.
Thank you
Attachments:
Voltage.vi ‏218 KB

Hi,
Did you try doing a search on the forum for error code 50103? (Leave out the "-" sign.) This question has been asked many, many times before.
You need to put all of your analog input channels into a single task. You only have one clock to work with. You get error code -50103 because you are trying to use that clock for three separate tasks.
Looking at your VI, it seems obvious that's the error you're getting even though you don't specify. Searching the forum for that error code will yield plenty of information for you which should be helpful (although I already told you what the problem is and how to fix it -- some of the posts will go further in-depth for you...I just don't really feel like re-typing all of the information when it's already available).
For examples of how to properly perform a multichannel acquisition, look under "Help...Find Examples...Hardware Input and Output...DAQmx...Analog measurements..." You'll find a lot of example code there which should help you.

Error -50103 when I am trying to access two channels on USB 6366 board in the same time

I am trying to use two DAQmx tasks attempting to access two channels from
USB-6366 in the same time. But it gives me an error Error -50103. So I looked
online and find out it says ' It is not possible to have multiple DAQmx tasks
attempting to access the same physical device. '. So I am wandering how can
collect data from my ai0 and ai1 channels in the same time? Here is my code,
and please help me out. Thanks very much
Attachments:
error_-501013.vi ‏27 KB

Simple - use a single task with multiple channels. Surely the answers in all of the related posts said that. The channel list is just dev1/ai0:1.

AS3: How to access and control embedded sounds in an external swf?

I rarely use sounds in AS3/Flash. I am using Flash Pro CS6, but I can't seem to figure out how to access, control (play, stop, etc) sounds embedded in an external SWF loaded into the main SWF.
It's easy to control them when embedded on the main swf. However, on an externally loaded SWR, I get all kinds of errors. For this app, I really need to embed them in the external SWF.
I read several solutions, but none seem to work.
I embed the sound an mp3 file called soundSegment1.mp3 using Flash CS6 import tool and then open the actionscript properties panel on flash to select the class name: SoundSegment1. Then I edit the class code and create a file called SoundSegment1.as and it's saved right next to my document class main.as in the same directory. The code of the SoundSegment1 class looks like this:
package {
    import flash.media.*;
    public class SoundSegment1 extends Sound
        public function SoundSegment1 ()
            // no code in here
        public function playSound()
            var soundSegment1:Sound = new SoundSegment1();
            var channel:SoundChannel = soundSegment1.play();
Then, in my main.as, I have done several attempts to play this sound such as:
var fileLocation:URLRequest = new URLRequest(SWFToLoad); loader.load(fileLocation); loader.contentLoaderInfo.addEventListener(ProgressEvent.PROGRESS, progressListener); loader.contentLoaderInfo.addEventListener(Event.COMPLETE, completeListener); loader.contentLoaderInfo.addEventListener(Event.INIT, initListener);
function initListener(e:Event):void // I also placed this code on the completeListener and it didn't work {      loader.content.soundSegment1.playSound(); // doesn't work. }
I get:
Line XXX 1061: Call to a possibly undefined method playSound through a reference with static type flash.display:DisplayObject.
or, I also read that I should be able to do something like this anywhere in the Main.as file:
var theClass:Class = Class(loader.content.getDefinitionByName("SoundSegment1")); var theSound:theClass = new theClass(); theSound.play() //doesn't work either.
I also tried on the completeListener:
var TheClass:Class = e.target.applicationDomain.getDefinition("SoundSegment1") as Class; var theSound:TheClass = new TheClass();
theSound.play() //doesn't work either.
I get:
ReferenceError: Error #1065: Variable SoundSegment1 is not defined. at flash.system::ApplicationDomain/getDefinition()
I am stuck and I really need to get this to work. I would be genuinely grateful for your help.
Thank you in advance for any help provided. I really need to get it to work, because I can't simply embed them in the main SWF or load them individually externally one by one.
Thanks again!

THANK YOU!
I think your code may be over my head though. I think you are using an anonymous function which is not something I am familiar with (but I want to learn about if it's useful).
I also don't know where the classS came from. I see that it's a parameter sent along with the event, but I don't really see where that came from.
Someone at: http://www.kirupa.com/forum/showthread.php?305098-Playing-a-embedded-sound-in-an-external- swf&p=2658098#post2658098
Is showing what seems to be an easier solution, but my problem there is I can't access the source file of the "child" swf.... ayayay.....
I am going to tinker with your solution and see if it gets me anywhere. Thanks so much for your help again.

Capture single channel in c++

Hi,
I'm trying to write a simple C++ routing (Visual C++) using the NIDSA functions that generates a sine wave and captures the response data.
I can generate a sine wave using NIDSA_configure_source(), but I can't figure out how to get the response data.
I tried calling NIDSA_configure_capture_buffer() and then NIDSA_read_capture_single_chan() but then I get an "Unknown Error" from NIDSA_read_capture_single_chan(). (Error code = 0xffffd5d0)
Sample Code:
rc = NI4551_ConfigureSource(1,0);
// configure capture buffer
rc = NI4551_ConfigureCaptureBuffer(numMeasurements);
// read single channel
rc = NI4551_ReadSingleChannel("0", numMeasurements, pResult);
rc = NI4551_ConfigureSource(0,0);
I don't know if I've got the correct functions to generate the sine wave and capture data or if I'm even calling them in the correct order.
Is there any sample code out there??
Thanks!

Hello,
You have specified a resource descriptor for the source task but when you are calling the capture commands you have not set up an initialize function that tells the program what board to use. For instance try using the NIDSA_init and then use that session to pass to the other function calls such as NIDSA_configure_capture_buffer() etc. I have attached some example code that reads from the board and demonstrates the analog triggering capabilities of the board. I hope this helps. Please let me know if you have any questions after exploring these resources.
Regards,
Shea C
Applications
NI
Attachments:
455x Analog Trigger.zip ‏6 KB

Multiple Endpoints Single Channel

I am working on a project, that requires instancing of our
flex application. One idea that I came up with was to allow for
multiple urls to access the same data based on several variables.
One key components for this idea to work is being able to use
multiple endpoints with in the same channel in my
services-config.xml file.
Right now this is what my channel setup looks like.
<channels>
<channel-definition id="cfamf"
class="mx.messaging.channels.AMFChannel">
<endpoint uri="
http://admin.mydomain.com/flex2gateway/"
class="flex.messaging.endpoints.AMFEndpoint"/>
<properties>
<polling-enabled>false</polling-enabled>
<serialization>
<instantiate-types>false</instantiate-types>
</serialization>
</properties>
</channel-definition>
<channel-definition id="cfamf"
class="mx.messaging.channels.AMFChannel">
<endpoint uri="
http://user.mydomain.com/flex2gateway/"
class="flex.messaging.endpoints.AMFEndpoint"/>
<properties>
<polling-enabled>false</polling-enabled>
<serialization>
<instantiate-types>false</instantiate-types>
</serialization>
</properties>
</channel-definition>
</channels>
Ideally I would prefer it to act like this.
<channel-definition id="cfamf"
class="mx.messaging.channels.AMFChannel">
<endpoint uri="
http://admin.mydomain.com/flex2gateway/"
class="flex.messaging.endpoints.AMFEndpoint"/>
<endpoint uri="
http://user.mydomain.com/flex2gateway/"
class="flex.messaging.endpoints.AMFEndpoint"/>
<properties>
<polling-enabled>false</polling-enabled>
<serialization>
<instantiate-types>false</instantiate-types>
</serialization>
</properties>
</channel-definition>
</channels>

one AP will only serve a single channel per spectrum. If you have multiple SSID they can be on the same channel with no issue, so long as you're not running more than 4-5. After that you start to cause issues inside your own network.
If you absolutely had to run them on different channels, you would need multiple AP to accomplish that.
But as I said, you shouldn't need to.
Steve
Sent from Cisco Technical Support iPhone App

Replicating MS Access single form record selectors functionality

I am very new to APEX.
I would like to rebuild and improve on all our departments MS Access userforms using APEX.
At the moment I am trying to replicate the standard MS Access "single form" view of a record in a database table, with the record selector navigation buttons (prev, next, new record).
I have scoured the internet and this forum but have not successfully found the solution.
I need to be able to select a subset of records from a view/table and present them on a page one at a time, so the user can scroll through them (prev, next) and make edits. Because of the amount of info in each record, the whole screen will be taken up by each record (hence the single form view).
I have created a form pagination process that is supposed to get the next/previous primary key value, however I can't seem to get the buttons displayed on the form that should be firing off these processes.
What combination of features should I be using to replicate this functionality? I am using the "Form on a table/view" style page at the moment.
Cheers,
Richard.

Hi
Even if you created a form pagination process, you need to "initialise" the PK field(s) -- by default, they are null and the pagination buttons will not show (this is very different from how access works).
You can do it using a conditional computation (e.g. selecting the min PK value when the PK field is null).
I hope this helps.
Luis

How to access Spectrasonics plug-in?

I'm brand new to Logic. I'm having trouble accessing a Spectrasonics Omnisphere plug-in that I installed. I checked the Library/Audio/Plug-ins/Components folder and I see a file 'omnisphere.component' yet when I'm in Logic I'm confused as to what to do. I click an insert box in a channel strip - select plug-in's - but there is only some apple effects to choose from.
Message was edited by: pianoman1976

I just bought Spectrasonics Omnisphere for my iMac. I am using the computer's default audio settings for now. I am using M-Audio KeyRig 49 for my MIDI keyboard controller. I am new to all this. I tried to use Garage Band (iLife 08) to access the plug in. I cannot. I installed Logic Express 7 to use as a "host sequencer". Since I am new to this, I queried Spectrasonics. They said i had to have a "host sequencer" to use Omnisphere. It cannot be used "on it's own." I cannot, or haven't found out how to access the Omnisphere plug in. Any help here would be appreciated as I am getting very frustrated.

How to access single channels of multichannel acquisition?

Similar Messages

Maybe you are looking for