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Saving time when typing relations involving inverses:NCMakeRelations

One can save time in inputting various types of starting relations easily by using the command NCMakeRelations.

In[12]:= <<NCMakeRelations.m             
In[13]:= NCMakeRelations[{Inv,y,1-y}]
Out[13]= {y ** Inv[y] == 1, Inv[y] ** y == 1, (1 - y) ** Inv[1 -
y] == 1,
    Inv[1 - y] ** (1 - y) == 1}

WARNING

It is traditional in mathematics to use only single characters for indeterminates (e.g., $ x$, $ y$ and $ \alpha$). However, we allow these indeterminate names as well as more complicated constructs such as

$\displaystyle Inv[x], Inv[y], Inv[1-x**y]$    and $\displaystyle Rt[x]   .
$

In fact, we allow $ f[expr]$ to be an indeterminate if $ expr$ is an expression and $ f$ is a Mathematica symbol which has no Mathematica code associated to it (e.g., $ f= Dummy$ or $ f=Joe$, but NOT $ f=List$ or $ f=Plus$). Also one should never use $ inv[m]$ to represent $ m^{-1}$ in the input of any of the commands explained within this document, because NCAlgebra has already assigned a meaning to $ inv[m]$. It knows that $ inv[m]**m$ is $ 1$ which will transform your starting set of data prematurely.

Besides $ Inv$ many more functions are facilitated by NCMakeRelations, see Section 25.0.1.


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Next: Saving time working in Up: Saving lots of time Previous: Saving lots of time   Contents   Index
NCAlgebra Project 2002-09-09