LabVIEW
Reading data from an XMLFile
Solved!
I was given a measurement file that is stored in XML from which I need to extract certain data. I have spend much of the morning going through all the XML posts I could find trying to figure out how to begin. I have also downloaded the GXML and EasyXML VI packages. The problem is that I can't seem to figure out how to actually use any of these files because all the examples I see are very nice small files and I am not sure how to apply them to my file.
The first thing I am trying to do is to extract data called CentralTilt. If I look at the XML map in Excel it would fall under Acquistions-> SystemConfig->Data. In Excel when I extract that data I get a column of about 1200 values. I am trying to do the same, but place them in an array in Labview.
Ultimately I need to do this of a several other values within the file and then perform some additional manipulation which is why I would like to try to automate this in Labview. I think if I can just get past this first hurdle of not really understanding how these different XML functions call on the file and parse out the data I should be able to figure the rest out. Some guidance would be appreciated. Thanks.
Unfortunately, I cannot post the file as it is too large, but I have a screenshot of the XML map.
Try something like this. The XPath expression may need to be modified to fit your data structure.
Ben64
Received some warnings while converting, you may have to replace some of the VIs used (Load and Close VIs).
Ben64
It loaded just fine and actually returned the very first value for the parameter I was looking for.
My next step will be to use this and augment it so it finds all the values. I believe this can be done using the Get All Matched Nodes. Let me know if I am wrong. Thanks!
@Cseaman wrote:
It loaded just fine and actually returned the very first value for the parameter I was looking for.
You're right, it can be done using Get All Matched Nodes. It will return an Array of Node References. Put the Get Node Text Reference.VI with its Close.VI in a FOR loop to read all matched nodes values.
Ben64
