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You can search the Frosty Drew Website for pages that deal with a topic you specify. Write an expression that contains one or more words that you feel might match the description of an interesting web page. The expression can be a single word, a list of words or an expression involving symbols for "and", "or" and "not" possibly grouped with parentheses. As an example, the search words Meade LX200 Telescope will make a match all Frosty Drew pages described with the words meade, lx200 or telescope. Search words are completely case insensitive. An asterisk "*" is a wildcard at the end of a word. It matches any remaining letters in the page description word. For example nebul* matches nebula, nebulosity, nebulae and nebulas. All references to a word are equally valid for a word* combination. "|" is a logical conjunction OR. If either (or both) of the words it separates matchs the description of a web page the result is true. You may omit the "|" symbol using simple spaces between the words. Thus TOM DICK HARRY and TOM | DICK | HARRY are equivalent expressions. "&" is the logical conjunction AND. Both words it separates must match the description of a web page for the result to be true. For example, "rocket&science" would match a page about rocket science but not a page about general science or simply rockets. "CUB* & DEN*" would match "Cubscout den" or "cub den" . It would not match "Cub pack" or "cubic" or "density" which would have been the case for "|" or a simple blank. |
"~" is the logical conjunction NOT. Only the word which follows it matters. If this word matches a description of a web page, then ~word will be false. If on the other hand the word doesn't match the description the result will be true. Care should be used because ~sword would cause the selection of every page in the website because none of them have a description of swords. "( )" are used to group portions of expressions. For example the expression "(true|false)&~(false&~true)" where true and false indicate words that match or miss match the web page description (respectively). The first parenthetical expression (true|false) is true because if either (or both) words match, the whole expression matches. Inside the second parentheses ~true will be evaluated first yeilding false which makes the expression ~(false&false) which reduces to ~false[that is true]. Combining true&true ultimately yeilds true so the page is displayed. Within a parenthetical level, ~ is evaluated first, then & is evaluated and finally | is evaluated. The order in which the pages are presented is in order by folder and file name. No attempt is made to find the best ordering. A word of caution. The search facility works correctly for well formed expressions. It attempts to detect improperly specified expressions and either "fix" them or indicate that the expression is not meaningful. |