Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Compact Widts in Metric Trees   The definition of $n$-width of a bounded subset $A$ in a normed linear space
$X$ is based on the existence of $n$-dimensional subspaces. Although the
concept of an $n$-dimensional subspace is not available for metric trees, in
this paper, using the properties of convex and compact subsets, we present a
notion of $n$-widths for a metric tree, called T$n$-widths. Later we discuss
properties of T$n$-widths, and show that the compact width is attained. A
relationship between the compact widths and T$n$-widths is also obtained.

23
The categories of this paper are: solv-int
17
The categories of this paper are: q-fin
11
The categories of this paper are: hep-lat
4
The categories of this paper are: cond-mat
0
The categories of this paper are: hep-ph
22
The categories of this paper are: chao-dyn
27
The categories of this paper are: comp-gas
28
The categories of this paper are: alg-geom
36
The categories of this paper are: cmp-lg
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
26
The categories of this paper are: bayes-an
32
The categories of this paper are: atom-ph
14
The categories of this paper are: math-ph
12
The categories of this paper are: nucl-th
13
The categories of this paper are: quant-ph