Character Filter Inclusive

by Norman T. Thornton
June 10, 2008

presented by PoeticWrites.org

Abstract

The Character Filter Inclusive (CFI) requires that all words of a given input text have all the characters of the CFI. Contrast the CFI with the Character Filter Exclusive (CFE) that requires words of a given input text be rejected if any characters of word match CFE characters. Thus, the union of sets in set theory is applicable.

Introduction

The CFI came out of work in Word Transformation Poetics, specifically the GraphicWord Tool although it finds general utility in forming word sets where the resultant set is the union of an input text with a filter.

Given word group G where g₁ to g_n are the ordered set of G elements (words) and filter F where f₁ to f_m are the elements (characters) of F, let the set R equal the result where filter F eliminates any g that does not have all the F elements and only the F elements. Thus,

if G{ man in air} and F{ a, n, m} then R{ man } --- since only "man" has all the letters of F and "man" does not contain any letters that are not in F, "man" qualifies for R
if G{ many in air} and F{a, n, m} then R{ } --- since "many" has the letter "y" that is not found in F, "many" is elimanted from R

Let F be the Character Filter Inclusive (CFI). Use the Character Filter Inclusive to find words that are only composed of the characters in the filter, thus, confine words to a graph region of the y-axis of a GraphicWord Poetics. However, contrast this with the Character Filter Exclusive (CFE) that eliminates any word that contains characters in the filter and thus confines words to graph regions of the y-axis. Yet, typically, the Character Filter Exclusive allows more words than the Character Filter Inclusive when CFI size (the number of characters in the filter) is compared to CFE size. The CFE allows more words than the CFI since the CFI imposes that all the characters of its filter must be present for a word to qualilfy as chosen. Of course, if the CFE has all 26 characters of the alphabet, no word could qualify as being chosen whereas if the CFE has all 26 letters of the alphabet, any word that has all 26 letters of the alphabet would be chosen! But, how many 26 letter words are there in English? In ordinary use, the CFE will be the more used of the two since it provides more words per typical text input.

The CFI is thus useful for finding words (for example, anagrams or palindromes) that ascribe with all of its letters to a particular character group.