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invoke node/Copy Selection (Diag)

Currently, for an array variable, changing an element requires the developer to read the array, update the element and write the array out. Whilst this is fine for simple cases with not sophisticated data flows, it becomes very cumbersome for cases when parallel processing is introduced. For instance, multiple loops updating an array of status flags.

At present, if two loops (which may be in different Vis) both execute a read-update-write operation on a global shared variable, data can be lost if the operations happen at similar times. Consider the following example:

Looking at the image above, let's imagine "array1" consists of two elements with values F and T respectively. Then the operation would happen as follows:

Step Number	Action taken	Array values
1.	Read "array1"	F and T
2.	Read "array1"	F and T
3.	Update "array1" element 0 to T	T and T
4.	Update "array1" element 1 to F	F and F
5.	Write to "array1"	T and T
6.	Write to "array1"	F and F

Hence all the data written by “Loop A” is lost. Putting user-defined locking using shared variables around the operations does not seem to work, presumably due to update rate of the locking variables.

What would be helpful to overcome these race conditions is to replicate the functionality present in other languages to do operations like a[3]=4 or printf(“%lf”,a[4]). In these cases, an atomic operation is performed to get or set the value in the defined memory location. The addition of this functionality to shared variables would be extremely powerful.

An example of such functionality could look something like this:

When comparing strings with the case structure, behavior at the time of the range specification is different from that of numeric type.

I have set a default case to case the other in the block diagram below.
If the default case, "B" is to be output.

You might think that it outputs the "A" none at first glance, but it will be "B" output of the block diagram of the second.

Block diagram

Output

This behavior is described in Help. It was also in the old version. It is probably specification.
It may be the reason for a bug if you write a program of string processing without knowing this specification.

I think that we should match the case, "c", which wrote "a" .. "c" in the case selector label.

Link：LabVIEW2013 Help - Entering Values for Each Case Structure Subdiagram

Quote:

String ranges
A range of a..c includes all strings beginning with a or b, but not c. String ranges are case sensitive. For example, a range of A..c behaves differently than a..c because LabVIEW uses ASCII values to determine a string range.

The function Excel Get Excel Location function in the NI Report Generation Toolkit takes an Excel cell address (e.g.A1) and returns row/column (array) indices (e.g. 0, 0). However, if a "non-cell" address, including a blank input, is input, the result is 0, 0, the same as if A1 was entered. I'd suggest that an index of -1, similar to the "illegal Array index", be returned for cell entries that don't parse as a Cell Address. Specifically, <blank> would return -1, -1 (which doesn't correspond to the legal cell address A1).

This illogcal behavior of the current function has messed up some functions I've written to manipulate Excel worksheets. My routines checked for indices "in range", but got fooled by the "wrong" 0, 0 returned by <blank>. So either I have to build a "validity check" before using this function or (better, in my opinion) the function needs to return legal indices only for legal inputs.

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Get number of bits of data types

Hi,

I am looking for a function that gives the number of bits (or bytes) that a given data type uses on disk and could not find it so far. LV types use constant number of bits for each specific data type, e.g. a string is always 8 bit, a single numeric is 32 bit and a double is 64 bit. It would be helpful to have a function that takes any data type as input and gives back the number of bits used to save the data on disk.

With this function one could write VIs that read/write binary files generic. Without this function I have one VI that reads double numerics from a binary file (e.g. the 4th number is on positioin 4*8) and a different VI to read an U8 numeric (the 4th number is on poistion 4*1). The only difference between those two VIs is the constant for a doulbe (8 bytes) and a U( (1 byte).

So basically I would prefer the "GetNumberofBytesOfDataType.vi" shown at the bottom of the attached example implemented as a LabVIEW native function.

Regards,

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Bit Bit windows detection

I have a idea for LV jitter analysis toolkit (JAT).

Please add some examples with "Clock Recovery by PLL Filter.vi" and "Clock Recovery by 2nd Order PLL.vi".

And, my customer previously used DPOJET as jitter analysis toolkit. DPOJET has very detailed manual.

http://www.av.it.pt/Medidas/Data/Manuais%20&%20Tutoriais/18%20-%20Real%20Time%20Oscilloscope%2020Ghz/CD2/Documents/DPOJET.pdf

He wants to switch from DPOJET to LV JAT. However, LV JAT does NOT have detailed manual.

If LV JAT doesn't have detailed manual, I think that LV JAT needs more examples.

Now, LV JAT 2013 has 8 exsample.

Multisim-LabVIEW cosimulation

#define for Rings or Enums

Offten I will get handed a PDF of something like this

#define PMC_STATUS_5V_ABOVE_POWERON 0x0001

#define PMC_STATUS_5V_ABOVE_BROWNOUT 0x0002

#define PMC_STATUS_12V_ABOVE_POWERON 0x0004

#define PMC_STATUS_12V_ABOVE_BROWNOUT 0x0008

#define PMC_STATUS_U31_PG 0x0010

#define PMC_STATUS_U30_PG 0x0020

#define PMC_STATUS_3P3_PG 0x0040

#define PMC_STATUS_USB_RESUME 0x0080

#define PMC_STATUS_U31_DCDC1_PG 0x0100

#define PMC_STATUS_U31_DCDC2_PG 0x0200

#define PMC_STATUS_U31_LDO3_PG 0x0400

I want a simple way to impor this into labview and doe bitampping besides this

which seems like a very messy solution to a thing that is very easy to do in every other language.

Time to call a dll !!!

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I use typecast a lot. It's the perfect function to turn clusters into a string and vice versa when doing tcp or udp communication. Unfortunately it breaks when the cluster contains a string or array. If I pass a cluster containing a five character string and a U32, it should give 9 characters out.

The main complication seems to be turning that same 9 character string back into a cluster, without size info on the string Type Cast doesn't know how many bytes go to the string. That could be pushed back to the user and require the cluster wired to the 'type' input to have the expected number of characters in the string or elements in the array.

I looked at Flatten To String, but if you pass a cluster containing a string it always prepends the string length in the flattened output.

I haven't yet had a chance to look at LV2013, maybe it's in there?

It would be helpful if the IMAQ Particle Analysis VI took as inputs:

Max Number of Particles

Maximum Analysis Time

It could then use these parameters to decide when to quit processesing the image and report back that it did not complete the operation via a boolean output or enumeration that indicates why it did not complete the processing.

In an automated vision system used count defects it is possible that the sample under test has an enormous amount of defects. In that case the user might want to call the sample grossly defective and they do not care if the exact number of defects (particles) are reported. Likewise, if the automated system has a fixed time frame over which it needs to process a sample this input would guard against that time frame being exceeded.

Greetings:

There were couple of related posts on Close Reference. I did a search and found these. I am posting it here for reference. Link1, Link2.

I am suggesting that anytime we use an item from Application Control palette or an instance where an application reference needs to be closed, a Close Reference item also be automatically placed in the block diagram. This would be very similar to how teststand handles Flow Control. So when a Close Reference is always dropped, it suggests good programming practice to close all references from the subVI/VI. Ofcourse LabVIEW will have to determine the best location to drop the Close Reference.

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IMAR Read QR Code VI

Hi,

I'm bit afraid to post this idea, because it seems to be I could overlook something.

There is no function which do the proper rounding (with 5 a a last digit as a hard limit) as below:

If the last digit is 5 o greater round up, otherwise round down.

An example:

(to simplify I use only one digit after dot)

0.1 -> 0

0.4 -> 0

0.5 -> 1

0.9 -> 1

1.1 -> 1

1.4 -> 1

1.5 -> 2

1.9 -> 2

2.1 -> 2

etc.

Now to satisfy this function you have to do coding like this (just for numbers with one digit after the dot):

Why to complicate so simple thing???

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I have several times found myself using variants to create various types of sorted ~~lookup tables~~ data sets. (Variants "sort" attributes/records by the name automatically, taking a performance hit when creating/adding to the variant, but wicked fast to retrieve a named attribute, and when getting a list of all named attributes they are returned "sorted".)

Now, in many/most of those scenarios, I find myself wishing I could just name the attribute with a numeric input without the hassle of converting the numeric to a string.

For example, if you read the file-property of all files in a folder tree and put various information for each file into a cluster (e.g. size, last modified date, name etc.), this cluster would become the "attribute" or "record" that you add to a variant for quick lookup later. Now, of course you have many ways to name the attribute(s) depending on what you want to do. In one case, you may want to retrieve file attributes based on the oldest (or newest) "last modified" time.. currently one way to do this is to "format into string" the "last modified" time stamp data and use that as the attribute name. If you are careful with how you format it to string, the sorted string list will come back oldest to newest (e.g. format it as YYYYMMDDHHMMSS to get a decimal string that sorts oldest (least) to newest (latest). (Note that when getting lists of files from LabVIEW, the order of the returned files does not appear to be sorted by "modified" or "created" dates.)

It would be nice if instead the "name" input would support usage of numeric inputs directly. If this was implemented at a low enough level, then the string conversion would not only be hidden from us (users), but potentially be completely removed as I picture the "name" at a low enough level is just a unique identifier anyway.. If this could be made to allow the "name" terminal to accept time-stamp data types, strings, I/U32 and DBL I would be very happy indeed!

Please discuss in comments if this is good, bad, impossible, possible etc. etc.

Thanks,

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LabVIEW Idea Exchange

invoke node/Copy Selection (Diag)

Network Published Shared Variable Array Handling

Behavior when you specify a string range to the case selector label

Property Node : type specifier refnum

Default for Excel Get Excel Location function

Texture subarray update for 3d control

Get number of bits of data types

Bit Bit windows detection

LV Jitter Analysis Toolkit: Please add some examples with "Clock Recovery by PLL Filter.vi" and "Clock Recovery by 2nd Order PLL.vi".

Multisim-LabVIEW cosimulation

#define for Rings or Enums

Case Structure - select frames : by name, but also by index

Time to call a dll !!!

Propagate Reentrant Options to Children

Update Type Cast to allow Clusters containing a string or array

IMAQ Particle Analysis Modifications

Close Reference - Auto Insert/Drop into Block Diagram

IMAR Read QR Code VI

Correcting round function / new correct round function

variant "name" input as numeric instead of string?