Editing Almost periodic function (section)

===Weyl almost periodic functions===
The space ''W''<sup>''p''</sup> of Weyl almost periodic functions (for ''p''&nbsp;≥&nbsp;1) was introduced by Weyl (1927).<ref>H. Weyl,   "Integralgleichungen und fastperiodische Funktionen"  Math. Ann., 97  (1927)  pp.&nbsp;338–356</ref> It contains the space ''S''<sup>''p''</sup> of Stepanov almost periodic functions. 
It is the closure of the trigonometric polynomials under the seminorm

:<math>\|f\|_{W,p}=\lim_{r\to\infty}\|f\|_{S,r,p}</math>

Warning: there are nonzero functions ''&fnof;'' with ||''&fnof;''||<sub>''W'',''p''</sub>&nbsp;=&nbsp;0, such as any bounded function of compact support, so to get a Banach space one has to quotient out by these functions.