The method it seems you are referring to could be scaling.
If you mean scaling every item in proportion to a new size, I usually use the document properties dialogue (SHIFT+CTRL+D) to change my document size (I mostly scale from A3 down to A4). I group the object on the page, then in the tool control bar I change my W and H to reflect a percent value.
To scale from A4 to A3 141% will resize it exaclty to scale down from A4 to A5 71% will resize proportionally provided you have the constrain proportion locked, these percent values will scale anything in the A Series of page sizes I don’t really work n the B or C series pages but hopefully this helps or gets on your way.
If you mean that you have a stand-alone svg file not opened in Inkscape that you wnat to resize to fit a certain document. So you have “fileinquestion.svg” saved as a A4 in your working directory but you want to proportionally fit “fileinquestion.svg” on a A3 page without having to open it. I use Scribus but instead of svg I use postscript or eps files. The way I use it is to set my Scribus page in the size I need it in then create an image frame to the document size. Get image will allow me to import the standalone file and set it to fit image to frame.
Hopefully that could work for you, I haven’t tested this method in Inkscape or at least I don't know if Inkscape is able to do this, maybe a script exists somewhere...
On Thu, 2014-09-11 at 14:56 -0400, john Culleton wrote:
I know that the vector components on an svg page can be expanded or contracted using Inkscape. But Suppose I have an Inkscape svg document that I want to make bigger or smaller to fit a different page size etc. I there a practical way to expand/contract the entire document and all its contents in proportion as well?