PuiseuxSeries¶

structured expression for Puiseux series¶

Calling sequence:¶

$\operatorname{PuiseuxSeries}(q, s)$

Parameters:¶

  • $q$, a positive rational number
  • $s$, an object of type series or $0$

Description:¶

  • $\operatorname{PuiseuxSeries}$ is an essentially inert function. It codes a Puiseux series as a ramification order and a Laurent series, except when the ramification order $q = 1$ and then the returned object is a Laurent series.
  • The name PuiseuxSeries is a `undocumented protected name', (it is used by RegularChains[AlgebraicGeometryTools][RegularChainBranches] with a different use to describe a Puiseux series). As a consequence, we first unprotect it and next we protect it as name in the package dcfun.

Example:¶

In [1]:
libname := libname, FileTools:-JoinPath(["maple","lib","dcfun.mla"],base=homedir):
In [2]:
 with(dcfun):
Out[2]:

We define two Puiseux series. When the ramification order is $1$, we obtain a Laurent series.

In [3]:
 s := PuiseuxSeries(2, series(1/(1 - 3*x)/x, x));
Out[3]:

$$\frac{1}{\sqrt{x}}+3+9 \sqrt{x}+27 x +81 x^{\frac{3}{2}}+243 x^{2}+O\! \left(x^{\frac{5}{2}}\right)$$

In [4]:
 s := PuiseuxSeries(1, series(1/(1 - 3*x)/x, x));
Out[4]:

$$x^{-1}+3+9 x +27 x^{2}+81 x^{3}+243 x^{4}+\mathrm{O}\! \left(x^{5}\right)$$