Count node issue

Hi,
This is my problem: a process selects some data in tables and returns:
<A>
 if data exists
</A>
or
<A> if data does not exist
</A>
I need to count the B nodes. I used countNodes function. It's works if at least one B node exists but returns a null exception if B does not exist !! to my mind, the function countNodes should return 0 ...
I'm wrong ?
So how to count node when data could not exist ? (catch a selectionFailure exception ?)
Thanks for your help,
Cyryl

closed

Similar Messages

Unable to Count Nodes using ora:countNodes , the count is always 0

B2B is connected to BPEL , the xsd used for the given xml is :
<?xml version="1.0" encoding="windows-1252" ?>
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"
xmlns="http://www.example.org"
targetNamespace="http://www.example.org"
elementFormDefault="qualified">
<xsd:element name="Root">
<xsd:complexType>
<xsd:sequence>
<xsd:element name="Batch">
<xsd:complexType>
<xsd:sequence>
<xsd:element name="Warehouse" type="xsd:string"/>
<xsd:element name="BatchDate" type="xsd:integer"/>
<xsd:element name="Revision" type="xsd:string"/>
<xsd:element name="OnHand" maxOccurs="unbounded">
<xsd:complexType>
<xsd:sequence>
<xsd:element name="ItemCode" type="xsd:string"/>
<xsd:element name="SOH" type="xsd:integer"/>
<xsd:element name="Quarantine" type="xsd:integer"/>
</xsd:sequence>
</xsd:complexType>
</xsd:element>
</xsd:sequence>
</xsd:complexType>
</xsd:element>
</xsd:sequence>
</xsd:complexType>
</xsd:element>
</xsd:schema>
Count nodes function used by me is :
ora:countNodes('receive_InventoryReconcilliation_receive_InputVariable','body','/ns2:Root/ns2:Batch/ns2:OnHand/ns2:ItemCode')
or
ora:countNodes('receive_InventoryReconcilliation_receive_InputVariable','body','/ns2:Root/ns2:Batch/ns2:OnHand/ns2:ItemCode')
I have tried using countNodes in above two ways.
Inspite of that i always get count of nodes as 0.
How should i resolve this issue ?
Thanks in advance,
Sasmit
Edited by: Sasmit on Jun 6, 2011 6:09 AM

Hi Sasmit...
i was facing a same problem recently...i can see the B2B adaptor giving the file as input to my BPEL process but the count is coming as zero...then what i did was..i tried copying the value of an element in the input variable...i cannot copy the value too...So, then i figured out that when i defined the document definition in B2B console, we will be giving the XSD file right...that schema file is not in sink with the file being picked up...may be i might have done amistake while generating the XSD file for a particular document in B2B Editor...then later i created the document definition i mean the xsd file in B2B Editor and used that new XSD file in my document definition...then i could access all the data in my BPEL process...
Just try this..,may be it helps.
Thanks,

ARIS - Solman Integration : Occurence copied node issue

Hi,
We are using ARIS - Solution Manager 4.0 Synchronization.
But, we encountered a big problem with synchronization.
That is as follows.
For example, there is following process - process step.
 Process Process Step
 ( Processing Subcontract P/O ) - ( Create Purchase Order )
 ( Processing P/O ) - ( Create Purchase Order )
In this case, we can create as follows:
< ARIS >
 Process Process Step ARIS GUID
 ( Processing Subcontract P/O ) - ( Create Purchase Order (A) ) - ( 8888 )
 ( Processing P/O ) - ( Create Purchase Order (B) ) - ( 9999 )
This is the way to create two process step individually by defintion functionality.
But, it's inconvenient because we must maintain the information of two process steps (A),(B) separately.
And, In this case, they have separate GUID. (They are different things)
But, ARIS supports the Occurence copy functionality.
With this functionality, we can make as follows:
< ARIS >
 Process Process Step ARIS GUID
 ( Processing Subcontract P/O ) - ( Create Purchase Order (A) ) - ( 8888 )
 ( Processing P/O ) - ( Create Purchase Order (A) ) - ( 8888 )
In this case, we can see this process step, "Create Purchase Order", below the two process,both.
But, That is one node physically, so it has a only one GUID.
And, we can change the information(T-CODE, Name) in only one side.
I think this is necessary and right concept.
But, when this process is synchronized to solman, following problem occurs,.
< Solution Manager >
 Process Process Step (ARIS GUID) SAP ID
 ( Processing Subcontract P/O ) - ( ) - ( ) - ( )
 ( Processing P/O ) - ( Create Purchase Order (A) ) - ( 8888 ) - ( ABCD )
This is the result synchronized to solution manger.
That is, because process step(A) is physically one, so it's transfered to solman only once.
Exactly speaking, that is originally transfered below the process "Processing Subcontract P/O"
and moved below "Processing P/O" again.
In conclusion, occurence copied node in ARIS is synchronized to solman only once as I know.
If this is right, I think it might be a very big problem in ARIS-SOLMAN integration part.
And, I guess this could be fixed because the Solman function module for ARIS Sync.,
"Z_SOLAR_NODE_ADD", has the import parameter "I_REF_GUID", and solman support the occurence copy(Reference copy) function.
My questions are as follows:
1) Is it right that occurence copied node in ARIS is transferred to solman only once?
2) Is there anybody who knows the plan of IDE or SAP with this problem?
Thanks for your help in advance.
Best regards,
jihyun cho

Dear Michael,
Thank you so much for help!!!
I created customer message about this issue, either.
And I got the reply from SAP they sent this message to the development support level which will be handled by IDS Scheer.
But, I didn't get any message from IDS yet.
If they would contact me, I will check when new feature will be avaliable. And I will share this plan with everyone.
And I knew Shortcut function was newly updated with SP15 for the first time thanks to your reply.
Thanks for your help again.
Best regards,
jihyun cho

Binary tree - counting nodes

i have got a binary tree and i need to write a method which can count the number of leaves.
i have written the code as
static int countLeaves(BinaryNode node) {
 if (node == null) {
 return 0;
 else if (node.left == null && node.right == null) {
 return 1;
 return countLeaves(node.left) + countLeaves(node.right);
}but, how can i put the method in the main funcion, i have tried
int leafCount = countLeaves(root);it gives an error message "non-static variable root cannot be referenced from a static context". How can i solve this problem? Thank you.

the code looks like:
public class BinaryTree<AnyType>
 public BinaryTree( )
 root = null;
 public BinaryTree( AnyType rootItem )
 root = new BinaryNode<AnyType>( rootItem, null, null );
 public void printPreOrder( )
 if( root != null )
 root.printPreOrder( );
 public void printInOrder( )
 if( root != null )
 root.printInOrder( );
 public void printPostOrder( )
 if( root != null )
 root.printPostOrder( );
 public void makeEmpty( )
 root = null;
 public boolean isEmpty( )
 return root == null;
 public void merge( AnyType rootItem, BinaryTree<AnyType> t1, BinaryTree<AnyType> t2 )
 if( t1.root == t2.root && t1.root != null )
 System.err.println( "leftTree==rightTree; merge aborted" );
 return;
 if( this != t1 )
 t1.root = null;
 if( this != t2 )
 t2.root = null;
 public BinaryNode<AnyType> getRoot( )
 return root;
 private BinaryNode<AnyType> root;
 static int countLeaves(BinaryNode node) {
 if (node == null) {
 return 0;
 else if (node.left == null && node.right == null) {
 return 1;
 return countLeaves(node.left) + countLeaves(node.right);
 static public void main( String [ ] args )
 BinaryTree<Integer> t1 = new BinaryTree<Integer>( 1 );
 BinaryTree<Integer> t3 = new BinaryTree<Integer>( 3 );
 BinaryTree<Integer> t5 = new BinaryTree<Integer>( 5 );
 BinaryTree<Integer> t7 = new BinaryTree<Integer>( 7 );
 BinaryTree<Integer> t2 = new BinaryTree<Integer>( );
 BinaryTree<Integer> t4 = new BinaryTree<Integer>( );
 BinaryTree<Integer> t6 = new BinaryTree<Integer>( );
 t2.merge( 2, t1, t3 );
 t6.merge( 6, t5, t7 );
 t4.merge( 4, t2, t6 );
 // i want to run the method countLeaves here
 int leafCount = countLeaves(root);
 System.out.println("Number of leaves: "+leafCount);
}

Context with counter mapping issue

I need help with a mapping issue.
I have a source document that has multiple line items which in turn contains multiple item texts. This structure has been simplified below.
Source Sample
<DOCUMENT>
---<LINEITEM>
<ITEMFIELD>itemfield</ITEMFIELD>
<ITEMTEXTS>
<TEXT>text 1</TEXT>
</ITEMTEXTS>
<ITEMTEXTS>
<TEXT>text 2</TEXT>
</ITEMTEXTS>
---</LINEITEM>
</DOCUMENT>
Source Structure
DOCUMENT 1..1
LINEITEM 0..unbounded
ITEMFIELD 0..1
ITEMTEXTS 0..unbounded
In the target structure, I need to output each line item with a counter to represent the line item number. Also, I need to output each item text with the line item number it corresponds to:
Target Sample
<DOCUMENT>
---<LINEITEM>
<ITEMNUMBER>1</ITEMNUMBER>
<ITEMFIELD>itemfield</ITEMFIELD>
---</LINEITEM>
---<ITEMTEXTS>
<ITEMNUMBER>1</ITEMNUMBER>
<TEXT>text 1</TEXT>
---</ITEMTEXTS>
---<ITEMTEXTS>
<ITEMNUMBER>1</ITEMNUMBER>
<TEXT>text 2</TEXT>
---</ITEMTEXTS>
</DOCUMENT>
Target Structure
DOCUMENT 1..1
LINEITEM 0..unbounded
ITEMNUMBER 1...1
ITEMFIELD 0..1
ITEMTEXTS 0..unbounded
ITEMNUMBER 1..1
TEXT 1..1
I do not know how to match the ITEMNUMBER in the ITEMTEXTS target structure with the corresponding LINEITEM target structure. Can anyone help me with this?
Regards,
JM

James,
I've tried both 1.2 release and 2.0 (v20091121-r5847) but received the same result - empty Map.
Moreover, for both versions the following string was absent in deployed XML file:
+<direct-key-field table="PARAM_SESS" name="PARAM_NAME" xsi:type="column"/>+
Therefore, on application initialization I have got an exception: org.eclipse.persistence.exceptions.DescriptorException with message This descriptor contains a mapping with a DirectMapMapping and no key field set.
So I was forced to add the line manually.
This seems buggy to me...
Regards,
Alexey

Smartform - Command Node Issue

Hi Super-Techies,
I am facing a strange issue in smartform. When I am using a command node to trigger a page, in the main window 1 table needs to get triggered (but it si not triggering). When I try to print the same table without any command node (i.e. in the same page) its working fine and the table data is being displayed.
But when I make use of command node to trigger to new page, All other windows are getting executed except the main window table.
Note; I have made use of 2 tables in main window. Normally 1st table should print, once new page is triggered, 2nd table should print and not the 1st one.
Can anyone help me out of this strange issue.
Thanks in Advance,
Vinit

Hi Vinit ,
In order to print data you require upon using command node , you need to display it on a secondary window.
Steps :
1) create secondary window .
2) provide table n related details .
3) u need not have a main window (optional) ;as data in main window won't be displayed.
This is the way I resolved the same issue .Hope it helps .
Thanks & regards,
Prakrita .

Cycle Count Reservation Issue in Item Supply/Demand Form

Hi
Few of the inventory items are stuck with Cycle Count Reservation in Item Supply/Demand Form. The Identifier field is empty. It is not tied to any sales order or PO . I checked the On hand quantity(on-hand quantity form) and the current on hand (Item Supply/Demand form) both are same. Could not able to figureout what went wrong and how the cycle count reservations are created. Even after performing the Cycle counting on these items, it did not consumed these reservations and releaved those reservations.
Could anyone suggest me please in what scenrios we get this issue and how to eliminate these records from the Item Supply/Demand Form. we are on 11.5.10.2 INV and WMS RUP4.
Thank You!
Krishna

CC reservations can be triggered by Curtail (Short) picks on mobile gun. When this happens the ATR qty gets decremented by this Qty by putting a CC reservation.
This can also be deleted from front end by changing the demand source to acc/acc alias, save and then delete.
Karthik

Visual Admin - Dispatcher - Monitoring Node issue

Hi all,
On a PI 7.0 SP13,
In visual admin, the monitoring node of the dispatcher section doesn't start fully :
Only both tabs "Properties" and "Additional Infos" are available.
When we try to start the Monitoring service manually, we got the following error message :
Start service Monitoring
java.rmi.RemoteException: Could not start service monitor on cluster ID 4226000; nested exception is:
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Do you have an idea to solve this issue.
Thanks a lot in advance
Edited by: Jean-Charles on Feb 14, 2008 5:02 PM

It is correct one
sorry
The monitoring service is red cross marked as it is not started. when we do rigth click and start we have the message quoted above...

Employee Head Count Planning issue

Dear Gurus,
I hope you are doing good...
We have requirement in our project which is User wants to enter HeadCount Working days to different cost centers.
Existing Configuration :
1) We have mapped employees to respective cost centers(Fixed)
2) User can enter working hours data for that cost center with out an issue
Requirement
User has that flexibility to select different cost centers and the entered working hours data needs to be saved.
Ex : Employee 10001 is mapped to Cost Center 12345.
Process - 1)Employee 10001 working hours mapped to Jan , Feb and March to cost center 12345.
2) Employee 10001 working hours mapped to Apr , May , Jun to Cost center 1236.
In the above case first instance it is possible because we have maintained this employee under 12345 cost center as hierarchy.
How we need to achieve the second instance since we are not able to map to multiple cost centers.
Please can any one help us in this issue.
Regards,
Satish

Hi Satish,
What do you mean by mapping? Do you have costcenters as nodes in employee dimension?
Vadim

Counting Nodes

Noob question.
This statement:
var nTableLength = TableKM.nodes.length;
is intended to count the child objects (rows) of a table which in my case should be a value of 3.
But the value in the debugger indicates that it is counting the children of the rows which are cells, a value of 6.
Is there a way to limit the counting to immediate child objects?
Thx.

You want to count the rows as they are the repeating object, not the table. If you had repeating tables your code would work.
And for .length I think you might need to use resolveNodes() (I'm at home now, just going off the top of my head):
var oRows = xfa.resolveNodes("TableKM.Row1[*]");
var nLength = oRows.length;
You can also use the Instance Manager to count:
var nLength = TableKM._Row1.count;

Unable to count nodes

Hi,
In a BPEL process I am working on there is an assignment activity where I assign the count of nodes as a result of a database query. This assignment is failing and am not able to figure out why.
Here is the bpel fragment for the assignment
*<assign name="Assign_1" bpelx:validate="yes">*
*<copy>*
*<from expression="ora:countNodes(bpws:getVariableData('Receive_1_receive_InputVariable','VvwshFmsHeadersCollection','/ns3:VvwshFmsHeadersCollection/ns3:VvwshFmsHeaders/ns3:vvwshFmsDetailsCollection/ns3:VvwshFmsDetails'))"/>*
*<to variable="FMSDetailCount"/>*
*</copy>*
*</assign>*
I am polling the database for some parent-child records. The intention is to count the number of child records in the collection.
Thanks in advance for your time and help. Please let me know if additional information is required.
Harish

Hi,
Just to be sure, my first solution is different from your solution, this is the one you tried ?
Mine : ora:countNodes('Receive_1_receive_InputVariable','VvwshFmsHeadersCollection','/ns3:VvwshFmsHeadersCollection/ns3:VvwshFmsHeaders/ns3:vvwshFmsDetailsCollection/ns3:VvwshFmsDetails')
Yours : ora:countNodes(bpws:getVariableData('Receive_1_receive_InputVariable','VvwshFmsHeadersCollection','/ns3:VvwshFmsHeadersCollection/ns3:VvwshFmsHeaders/ns3:vvwshFmsDetailsCollection/ns3:VvwshFmsDetails'))
romain.

WPC 7.0 Navigation node issue

Hi All - I am on WPC 7.0 and we did all the needed configuration for WPC 7.0, I have created a new website in WPC and publish it . I also created a Site Navigation and apply it to the Folder below my editor role.
Everything looks good but when I navigate to the Editor role I don't see the webpage under my WPC created website. This is the message I am getting "No content available for this navigation node"
Is there a known issue with WPC 7.0 which is causing this issue?
Thanks,
-Ash

We had similar issue. SAP replied to our OSS message and asked us to patch WPC component.
Thanks,
Raj

How to count nodes?

I'm new to DOM and am trying to understand the node hierarchy structure. I have the following sample XML file.
To understand what constitutes a "Node", I count and print the child nodes that are within the "slideshow" node. The result I get is that there are 5 nodes and the node names are: #Text, slide, #Text, slide, #Text
Can anyone explain to me how--based on the xml file below, there are 5 nodes within the slideshow element?

<slideshow title="Sample Slide Show" date="Date of publication" author="Yours Truly">
 <slide type="all">
 <title>Wake up to WonderWidgets!</title>
 </slide>
 <slide type="all">
 <title>Overview</title>
 <item>Why
 WonderWidgets
 are great</item>
 <item/>
 <item>Who buys WonderWidgets</item>
 </slide>
</slideshow>

#Text nodes are Whitespace nodes.
Refer to http://java.sun.com/xml/jaxp/dist/1.1/docs/tutorial/dom/2b_display.html

Cluster Node Issue Content Server

Hi ,
I have configure 2 node cluster Content Server. I have one issue only from one box I can not see node2 in admin server. For example, I have test1 and test2 box as node1 and node2. From admin server on test1 box I can not able to connect to test2. But same time I can connect to both the server from test2 box.
Please see error I am getting.
Need help resolving this issue.
Regards,
Jigar
Copyright(C) 1996-2007 Oracle, Inc. All rights reserved.
Ready and waiting for connection on port 4440, PID 7236 (idc42)
idcadmin 08.12 13:37:57.119 IdcServerThread-1 requestRequiresRemoteServer() checking admin 'Prodcs1_admin', node name 'ecmprod1.sjrwmd.com'
idcadmin 08.12 13:37:57.123 IdcServerThread-1 Executing command: [opt/oracle/ucm/cs1/admin/bin/UnixProcCtrl, exec, /opt/oracle/ucm/cs1/etc/idcserver_query]
idcadmin 08.12 13:38:07.977 IdcServerThread-2 requestRequiresRemoteServer() checking admin 'Prodcs1_admin', node name 'ecmprod1.sjrwmd.com'
idcadmin 08.12 13:38:07.978 IdcServerThread-2 Executing command: [opt/oracle/ucm/cs1/admin/bin/UnixProcCtrl, exec, /opt/oracle/ucm/cs1/etc/idcserver_query]
idcadmin 08.12 13:38:08.071 IdcServerThread-2 requestRequiresRemoteServer() checking admin 'Prodcs1_admin', node name 'ecmprod2.sjrwmd.com'
(internal) 08.12 13:38:08.080 IdcServerThread-2 !csUnableToConnect2,127.0.0.1|164.51.112.14|164.51.112.18,4440-exception stack
intradoc.common.ServiceException: !csUnableToConnect2,127.0.0.1|164.51.112.14|164.51.112.18,4440
 at intradoc.provider.SocketOutgoingConnection.createSocket(Unknown Source)
 at intradoc.provider.SocketOutgoingConnection.connectToServer(Unknown Source)
 at intradoc.provider.SocketOutgoingProvider.createConnection(Unknown Source)
 at intradoc.provider.SocketOutgoingProvider.createRequest(Unknown Source)
 at intradoc.admin.AdminService.doRequestRemoteAdminService(Unknown Source)
 at intradoc.admin.AdminService.loadAllIdcServerData(Unknown Source)
 at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
 at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
 at java.lang.reflect.Method.invoke(Method.java:585)
 at intradoc.common.IdcMethodHolder.invokeMethod(Unknown Source)
 at intradoc.common.ClassHelperUtils.executeMethodEx(Unknown Source)
 at intradoc.common.ClassHelperUtils.executeMethod(Unknown Source)
 at intradoc.server.Service.doCodeEx(Unknown Source)
 at intradoc.server.Service.doCode(Unknown Source)
 at intradoc.server.ServiceRequestImplementor.doAction(Unknown Source)
 at intradoc.server.Service.doAction(Unknown Source)
 at intradoc.server.ServiceRequestImplementor.doActions(Unknown Source)
 at intradoc.server.Service.doActions(Unknown Source)
 at intradoc.admin.AdminService.doActions(Unknown Source)
 at intradoc.server.ServiceRequestImplementor.executeActions(Unknown Source)
 at intradoc.server.Service.executeActions(Unknown Source)
 at intradoc.server.ServiceRequestImplementor.doRequest(Unknown Source)
 at intradoc.server.Service.doRequest(Unknown Source)
 at intradoc.server.ServiceManager.processCommand(Unknown Source)
 at intradoc.server.IdcServerThread.run(Unknown Source)
Caused by: java.net.UnknownHostException: 127.0.0.1|164.51.112.14|164.51.112.18
 at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:177)
 at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:366)
 at java.net.Socket.connect(Socket.java:519)
 at java.net.Socket.connect(Socket.java:469)
 at java.net.Socket.<init>(Socket.java:366)
 at java.net.Socket.<init>(Socket.java:179)
 at javax.net.DefaultSocketFactory.createSocket(SocketFactory.java:196)
 ... 26 more

Hi!!
First
What is ECM Enterprise content management?
What is Stellent
What is Standard cluster content server?
Is this more than product or that is one product and which one is for cluster on windows 2003
Do I need to install content server standalone for every node with IntradocDir different to clusternodeIntradocDir before going to install cluster server
I have
Second
When I try to install cluster server this error displayed to me
D:\CS10gR3\UCM\ContentServer\win32>Installer -set-ClusterNodeIntradocDir=f:/oracle/ucm/server/stelletnt/ucm01 -set-ClusterNodeName=ucm01 -set-ClusterNodeAddress
=101.101.102.196 -set-ClusterBinDirRule=shared ConfigureClusterNode
Unable to find file "ConfigureClusterNode".
The file wait.dat wasn't removed.
I find release note that describe problem with -set- it correct to set and still same error appears
Thank you for cooperation

What am I doing wrong with this filter (counter/frequency issue), probably another newb question.

I extracted the part of my VI that applies here. I have a 6602 DAQ board reading a counter for frequency, using a Cherry Corp proximity sensor. Getting a lot of noise and errant ridiculously high readings. Speed of shaft which it's measuring is currently 2400rpm with one pulse per revolution so 40hz.
Trying to use the express filter VI to clean up the signal and ignore anything over, say, 45hz and under 35hz. No matter what setting I choose I continually get the 20020 error, Analysis: The cut-off frequency, fc, must meet: 0 <= fc <= fs/2. I know this relates to sample period somehow, but for the life of me I can't understand what I'm doing wrong.
I used this VI without filtering on bench tests with a hand-drill and got perfect output every time. Now it's on the machine and being erratic. Any help here will ease my stress level significantly, thanks.
VI attached
Still confused after 8 years.
Attachments:
RPM.vi ‏92 KB

Hello Ralph,
I'm not sure about mounting your sensor to your rig, but I can provide a couple ideas about the filtering. Depending on the type of noise, the digital filters on the PCI-6602 could help eliminate the behavior you are seeing. If the noise manifests as a "glitches" or a bouncing signal, you could use another counter with a minimum period to help eliminate the noise. This concept is discussed in greater detail in this KnowledgeBase. I noticed that you are using NI-DAQmx; the practical application of the digital filters on the PCI-6602 in NI-DAQmx is discussed in this KnowledgeBase. A more detailed description of the behavior of these filters is provided in the NI-DAQmx Help (Start>>All Programs>>National Instruments>>NI-DAQ) in the book entitled "Digital Filtering Considerations for TIO-Based Devices".
I also wanted to comment on your original post and explain why you were receiving error -20020. For convenience, I have copied the text of the error code below.
Error -20020 occurred at an unidentified location
Possible reason(s):
Analysis: The cut-off frequency, fc, must meet: 0 <= fc <= fs/2.
I think you may have misunderstood exactly what the Filter express VI does. The Filter express VI takes a series of values in a waveform and performs filtering on those signals. So, it will look at a waveform made up of X and Y values and apply the defined filter to this waveform. Specifically in your application, the cut-off frequency (fc) is the Upper Cut-Off level that you specified in the Filter express VI; any frequency components of the waveform outside of the range you have defined will be filtered. The fs is the sample rate based on the data that you wire to the Signal input of the Filter express VI. In your VI, this data is coming from the DAQ Assistant. So, fs will be the sample rate of the DAQ Assistant and is associated with the rate at which points are acquired. The sample rate does NOT relate to the bandwidth of the signal, except that the Nyquist theorem tells us that the sample rate must be at least twice the signal bandwidth in order to determine periodicity of the signal. So, in this case, the sample rate of the DAQ Assistant would need to be at least double the high cut-off frequency.
However, you are performing a frequency measurement using a counter. I think this is where the confusion comes in. For the frequency measurement using a counter, the DAQ Assistant returns a decimal value which represents the rate of the pulse train being measured by the counter. It does not return the actual waveform that is being read by the counter. It is this waveform that would be band-pass filtered to eliminate frequency content outside of the filter's bandwidth. Instead of the Filter express VI, I would recommend that you simply discard values that are outside the range you specify. I have modified the code you posted earlier to perform this operation. The image below shows the changes that I made; rather than using the Filter express VI, I simply compare the frequency to the "Low Threshold" and "High Threshold". I use a Case structure to display the value on if it is within the limits. Otherwise, I display a "NaN" value. I have also attached the modified VI to this post.
Message Edited by Matt A on 09-04-2007 07:58 PM
Matt Anderson
Hardware Services Marketing Manager
National Instruments
Attachments:
RPM (Modified).JPG ‏17 KB
RPM (modified).vi ‏72 KB

Count node issue

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