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Background information:
The width and height attributes in the root svg element of an svg file determine the size of the viewport, in other words the size of the svg document when it is viewed. The coordinates of the objects in the svg file are specified in user space, which is different from the viewport space. The viewBox attribute in the root svg element defines the rectangle in user space that should be mapped to the edges of the viewport. The preserveAspectRatio attribute in the root svg element determines how this mapping takes place. The This mapping can use uses one of three possible methods: "stretchmeet", "meetslice" or "slicenone". See http://www.w3.org/TR/SVG11/coords.html#ViewBoxAttribute and http://www.w3.org/TR/SVG11/coords.html#PreserveAspectRatioAttribute for more detailed information.
Aligning text within svg text objects
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