" Why are attributes assigned in different order than svg file?"
Not sure, as I never used proXML (I use Processing's XMLElement or Java's standard XML handling), but the order of attributes is indifferent in XML. The library probably puts them in a hash map, which doesn't keep the order.

" Why is transform NOT EQUAL?"
Because you should never compare strings with ==
See String reference.

" Is this the correct syntax?"
The syntax looks OK, you might have an error elsewhere.
But if you " know [that] setAttribute() is not included in proXML", you probably get an error by calling a non-existing method on XMLElement.

Why are you trying to do?
- Manipulate the data once it is loaded? In this case, you probably must act on matrices and similar, not on XML elements that are already transformed to PShape.
- Automate the transformation of XML and then save back the XML? Then it might be the right approach. Processing's XML doesn't allow this, but as I wrote, you can use one of the standard XML processing facilities of standard Java, or use one of the many Java libraries around (most made before it was standard in Java), like JDom, Dom4j, Xom, and so on. See http://stackoverflow.com/questions/831865/what-java-xml-library-do-you-recommend-to-replace-dom4j for various recommendation. I found I plussed on the XMLTool recommendation, I don't remember using it, but I will follow my old choice and try it again...

XMLTool is very nice, with an easy to use API.
Example, to remove all transform attributes from g tags:

1. XMLTag doc = XMLDoc.from(new File("H:/Temp/Test.svg"), false);
2. for (XMLTag tag : doc.getChilds())
3. {
4.   if (tag.getCurrentTagName().equals("g"))
5.   {
6.     if (tag.hasAttribute("transform"))
7.     {
8.       tag.deleteAttribute("transform");
9.     }
10.   }
11. }
12. println(doc.toString());

And this isn't necessarily the shortest way to do it.
Example of making an XML from scratch:

1. XMLTag tag1 = XMLDoc.newDocument(true)
2.     .addRoot("html")
3.     .addTag("head").addText("one")
4.     .gotoChild("head")
5.     .addTag("title").addText("my title 1")
6.     .addTag("title").addText("my title 2")
7.     .addText("")
8. 
   
9.     .addTag("body")
10.     .addTag("number").addAttribute("type", "hexa").addText("0xCAFEBABE")
11.     .addText("two")
12.     .gotoChild("body")
13.     .addTag("bool").addText("true")
14.     .gotoRoot();
15. println(tag1.toString());

Quite nice, no?

But if you " know [that] setAttribute() is not included in proXML"

I was taking a chance that the software had more features than the web site.
It has a saveElement(), indicating that values can be changed.
I'm disappointed with proXML's website advertising that it enables easy manipulation of xml data.
Perhaps they should explain what they mean by that?

What I'm trying to do:

• Read the svg file.
• Modify it before Processing reads it.

Is that possible?

XMLTool is very nice, with an easy to use API.

I downloaded xmltool. When I selected it, this was automatically inserted into my code:

1. import com.mycila.xmltool.*;

But I can't find clear information about it as I did with proXML.
I'm not a professional programmer and find their manual confusing:



 

1. XMLTag doc = XMLDoc.from(new File("H:/Temp/Test.svg"), false);

I realized

> xmltool needs the path and file name (path not needed for normal svg files found in sketch Data folder).

> Windows users need to use forward slash (/) (they normally use backward slash ()).

1.   if (tag.getCurrentTagName().equals("g"))
2.   {
3.     if (tag.hasAttribute("transform"))
4.     {
5.       tag.deleteAttribute("transform");
6.     }
7. }
8. println(doc.toString());

Yes the PrintWriter worked.

1.   PrintWriter output;
2. //  output = createWriter("drawing08_new.svg"); // in same folder as sketch, not data folder
3.   output = createWriter("data/drawing08_new.svg"); // in data folder
4.   output.println(doc); // Write the doc to the file
5.   output.flush(); // Writes the remaining data to the file
6.   output.close(); // Finishes the file