writing Binary data

[npai]

Hi

I am trying to write a binary data file in single precision format. Writing the data is not a problem, but when I read the binary file, the data seems to have one extra zero at the start of the data. the data seems to shift towards right. Labview is introducing a zero point s at the start of the file which is making that shift. How to get rid of that extra point when I am writing the data. I am attaching the program I made to write the binary data file (write binary data) and also the file (file.zip)which I am trying to analyze. Also attaching the program to read the binary file.

Thanks,

[altenbach]

Works fine for me. I don't get the extra zero when reading the file.

Message Edited by altenbach on 01-19-2006 10:44 AM

[altenbach]

Sorry, I see the problem now.

You are talking about the binary file 1.spn.

You are writing it as a cluster, but read it as a SGL array. You need to write it as a SGL array to keep the universe in balance. 🙂

Here's ther relevant modification:

Message Edited by altenbach on 01-19-2006 10:55 AM

[npai]

Hi,

I tried that way, writing it the way u said, but when I am reading it, it gave me some unexpected results. I want the data in SGL format and as the write binary file.vi uses 8 byte little indian format, when reading it thru the Read SGL data vi I am not able to read it properly.

thanks

Nitin

[rolfk]

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@npai wrote:

Hi,

I tried that way, writing it the way u said, but when I am reading it, it gave me some unexpected results. I want the data in SGL format and as the write binary file.vi uses 8 byte little indian format, when reading it thru the Read SGL data vi I am not able to read it properly.

---

Of course data types for write and read should match. The function as in altenbachs picture will write doubles to the file. Just put a "To Single Precision" conversion node right after the log function and everything should be fine.

Rolf Kalbermatter

[npai]

Hi Rolf,

I tried that and still it is not working. I am attaching the two wave form graphs which I am getting. The first one is the one which I am reading which is one point off and the second is the one which it is supposed to write. There is a just one point difference in the two graphs.

[npai]

Hi Rolf,

I tried that and still it is not working. I am attaching the two wave form graphs which I am getting. The first one is the one which I am reading which is one point off and the second is the one which it is supposed to write. There is a just one point difference in the two graphs.

Thanks

Nitin

[altenbach]

OK, I found the problem. You need to wire a FALSE to the "prepend array size" input of the write operation.

Message Edited by altenbach on 01-19-2006 01:55 PM

[npai]

Thank you very much for that information.

I was trying everything for that, and that was just a small problem and I wouldn't be able to figure that out. Thank you very much

Nitin