design/tpl: Mostly-complex symbol index entries for Chapter 0

master
Mike Gerwitz 2021-05-11 11:33:12 -04:00
parent 7624bd2958
commit 7f4fc8e3b7
2 changed files with 75 additions and 26 deletions

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@ -20,11 +20,7 @@ When you see any of these prefixed with ``0.'',
\subsection{Propositional Logic}
\indexsym{\true,\false}{boolean}
\index{boolean!FALSE@\tamefalse{} (\false)}%
\index{boolean!TRUE@\tametrue{} (\true)}%
\indexsym\Int{integer}
\index{integer (\Int)}%
\index{logic!propositional}
We reproduce here certain axioms and corollaries of propositional logic for
convenience and to clarify our interpretation of certain concepts.
The use of the symbols $\logand$, $\logor$, and~$\neg$ are standard.
@ -49,14 +45,19 @@ We further use $\equiv$ in place of $\leftrightarrow$ to represent material
$p \infer (p\logor q)$ and $q \infer (p\logor q)$.
\end{definition}
\indexsym\neg{negation}
\index{negation (\ensuremath{\neg})}
\index{law of excluded middle}
\begin{definition}[Law of Excluded Middle]
$\infer (p \logor \neg p)$.
\end{definition}
\index{law of non-contradiction}
\begin{definition}[Law of Non-Contradiction]
$\infer \neg(p \logand \neg p)$.
\end{definition}
\index{De Morgan's theorem}
\begin{definition}[De Morgan's Theorem]
$\neg(p \logand q) \infer (\neg p \logor \neg q)$
and $\neg(p \logor q) \infer (\neg p \logand \neg q)$.
@ -72,59 +73,69 @@ $\equiv$ denotes a logical identity.
Consequently,
it'll often be used as a definition operator.
\begin{definition}[Logical Implication]
\indexsym{\!\!\implies\!\!}{implication}
\index{implication (\ensuremath{\implies})}
\begin{definition}[Implication]
$p\implies q \infer (\neg p \logor q)$.
\end{definition}
\indexsym{\true}{boolean, true}
\indexsym{\false}{boolean, false}
\index{boolean!FALSE@\tamefalse{} (\false)}%
\index{boolean!TRUE@\tametrue{} (\true)}%
\begin{definition}[Truth Values]\dfnlabel{truth-values}
$\infer\true$ and $\infer\neg\false$.
\end{definition}
\subsection{First-Order Logic and Set Theory}
\index{first-order logic}
\index{logic!first-order}
\indexsym\emptyset{set empty}
\indexsym{\Set{}}{set}
\index{set!empty (\ensuremath{\emptyset, \{\}})}
The symbol $\emptyset$ represents the empty set---%
the set of zero elements.
We assume that the axioms of ZFC~set theory hold,
but define $\in$ here for clarity.
% TODO: set-builder notation, union, intersection
\indexsym\in{set membership}
\index{set!membership@membership (\ensuremath{\in})}
\indexsym\union{set, union}
\indexsym\intersect{set, intersection}
\index{set!membership@membership (\ensuremath\in)}
\index{set!union (\ensuremath\union)}
\index{set!intersection (\ensuremath\intersect)}
\begin{definition}[Set Membership]
$x \in S \equiv \Set{x} \cap S \not= \emptyset.$
$x \in S \equiv \Set{x} \intersect S \not= \emptyset.$
\end{definition}
\indexsym\forall{quantification, universal}
\indexsym\exists{quantification, existential}
\index{quantification!universal (\ensuremath{\forall})}
\index{quantification!existential (\ensuremath{\exists})}
$\forall$ denotes first-order universal quantification (``for all''),
and $\exists$ first-order existential quantification (``there exists''),
over some domain.
\indexsym\logor{disjunction}
\index{disjunction (\ensuremath{\logor})}
\indexsym\exists{quantification, existential}
\index{quantification!existential (\ensuremath\exists)}
\begin{definition}[Existential Quantification]\dfnlabel{exists}
$\Exists{x\in X}{P(x)} \equiv
\true \in \Set{P(x) \mid x\in X}$.
\end{definition}
\indexsym\logand{conjunction}
\index{conjunction (\ensuremath{\logand})}
\indexsym\forall{quantification, universal}
\index{quantification!universal (\ensuremath\forall)}
\begin{definition}[Universal Quantification]\dfnlabel{forall}
$\Forall{x\in X}{P(x)} \equiv \neg\Exists{x\in X}{\neg P(x)}$.
\end{definition}
\indexsym\emptyset{set empty}
\indexsym{\Set{}}{set}
\index{set!empty (\ensuremath{\emptyset, \{\}})}
\index{quantification!vacuous truth}
\begin{remark}[Vacuous Truth]
By Definition~7, $\Exists{x\in\emptyset}P \equiv \false$
By \dfnref{exists}, $\Exists{x\in\emptyset}P \equiv \false$
and by \dfnref{forall}, $\Forall{x\in\emptyset}P \equiv \true$.
And so we also have the tautologies $\infer \neg\Exists{x\in\emptyset}P$
and $\infer \Forall{x\in\emptyset}P$.
\end{remark}
\indexsym\Int{integer}
\index{integer (\Int)}%
\begin{definition}[Boolean/Integer Equivalency]\dfnlabel{bool-int}
$\Set{0,1}\in\Int, \false \equiv 0$ and $\true \equiv 1$.
\end{definition}
@ -137,10 +148,22 @@ $\forall$ denotes first-order universal quantification (``for all''),
\subsection{Functions}
\indexsym{f, g}{function}
\indexsym\mapsto{function, map}
\indexsym\rightarrow{function, domain map}
\index{function}
\index{function!map (\ensuremath\mapsto)}
\index{map|see {function}}
\index{function!domain}
\index{function!codomain}
\index{domain|see {function, domain}}
\index{function!domain map (\ensuremath\rightarrow)}
The notation $f = x \mapsto x' : A\rightarrow B$ represents a function~$f$
that maps from~$x$ to~$x'$,
where $x\in A$ (the domain of~$f$) and $x'\in B$ (the co-domain of~$f$).
\indexsym\times{set, Cartesian product}
\index{set!Cartesian product (\ensuremath\times)}
A function $A\rightarrow B$ can be represented as the Cartesian
product of its domain and codomain, $A\times B$.
For example,
@ -151,6 +174,9 @@ For example,
\Set{\ldots,\,(0,0),\,(1,1),\,(2,4),\,(3,9),\,\ldots}.
\end{equation*}
\indexsym{[\,]}{function, image}
\index{function!image (\ensuremath{[\,]})}
\index{function!as a set}
The set of values over which some function~$f$ ranges is its \emph{image},
which is a subset of its codomain.
In the example above,
@ -170,6 +196,9 @@ We therefore have
f[] &= f[A].
\end{align}
\indexsym{()}{tuple}
\index{tuple (\ensuremath{()})}
\index{relation|see {function}}
And ordered pair $(x,y)$ is also called a \emph{$2$-tuple}.
Generally,
an \emph{$n$-tuple} is used to represent an $n$-ary function,
@ -190,13 +219,13 @@ Binary functions are often written using \emph{infix} notation;
\subsubsection{Binary Operations On Functions}
\indexsym{R}{relation}
Consider two unary functions $f$ and~$g$,
and a binary relation~$R$.
\indexsym{\bicomp{R}}{function, binary composition}
\index{function!binary composition (\ensuremath{\bicomp{R}})}
We introduce a notation~$\bicomp R$ to denote the composition of a binary
function with two unary functions.\footnote{%
The notation originates from~$\circ$ to denote ordinary function
composition,
as in $(f\circ g)(x) = f(g(x))$.}
function with two unary functions.
\begin{align}
f &: A \rightarrow B \\
@ -205,11 +234,14 @@ We introduce a notation~$\bicomp R$ to denote the composition of a binary
f \bicomp{R} g &= \alpha \mapsto f_\alpha R g_\alpha : A \rightarrow F
\end{align}
\indexsym\circ{function, composition}
\index{function!composition (\ensuremath\circ)}
Note that $f$ and~$g$ must share the same domain~$A$.
In that sense,
this is the mapping of the operation~$R$ over the domain~$A$.
This is analogous to unary function composition~$f\circ g$.
\index{function!constant}
A scalar value~$x$ can be mapped onto some function~$f$ using a constant
function.
For example,
@ -219,8 +251,12 @@ For example,
f \bicomp+ (\_\mapsto x) = \alpha \mapsto f_\alpha + x.
\end{equation*}
\indexsym{\_}{variable, wildcard}
\index{variable!wildcard/hole (\ensuremath{\_})}
The symbol~$\_$ is used to denote a variable that is never referenced.
\indexsym{\bicompi{R}}{function, binary composition, recursive}
\index{function!binary composition (\ensuremath{\bicomp{R}})!recursive (\ensuremath{\bicompi{R}})}
For convenience,
we also define $\bicompi{R}$,
which recursively handles combinations of function and scalar values.
@ -255,6 +291,16 @@ Unfortunately,
A vector is a sequence of values, defined as a function of
an index~set.
% TODO: font changes in index, making langle unavailable
%\indexsym{\Vector{}}{vector}
\index{vector!definition (\ensuremath{\Vector{}})}
\index{sequence|see vector}
\indexsym\Vectors{vector}
\index{real number (\ensuremath\Real)}
\indexsym\Real{real number}
\indexsym{\Fam{a}jJ}{index set}
\index{family|see {index set}}
\index{index set (\ensuremath{\Fam{a}jJ})}
\begin{definition}[Vector]\dfnlabel{vec}
Let $J\subset\Int$ represent an index set.
A \emph{vector}~$v\in\Vectors^\Real$ is a totally ordered sequence of
@ -270,6 +316,7 @@ This definition means that $v_j = v(j)$,
We may omit the superscript such that $\Vectors^\Real=\Vectors$
and $\Vector{\ldots}^\Real=\Vector{\ldots}$.
\index{vector!matrix}
\begin{definition}[Matrix]\dfnlabel{matrix}
Let $J\subset\Int$ represent an index set.
A \emph{matrix}~$M\in\Matrices$ is a totally ordered sequence of
@ -318,7 +365,8 @@ We can also add two vectors, and scale them:
\subsection{XML Notation}
\index{XML}
\indexsym{\xml{<>}}{XML}
\index{XML!notation (\xml{<>})}
The grammar of \tame{} is XML.
Equivalence relations will be used to map source expressions to an
underlying mathematical expression.

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@ -77,6 +77,7 @@
\newcommand\Matrices{\ensuremath{\Vectors^{\Vectors^\Real}}}
\let\union\cup
\let\intersect\cap
\let\infer\vdash
\newcommand\len[1]{\ensuremath{\left|#1\right|}}