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ht://Dig Detailed Help File
Contents:
Our indexing system reads the AMSAT-NA site once per week and the AMSAT-UK site several times a day. The amsat-bb and sarex mailing lists from 1998 are grouped together inder 'Mailing Lists' and are updated hourly.. The system compiles a complete, full-text index of HTML pages, plain text files, Postscript files, etc..
To keep the index within acceptable limits, the process is bound by the following rules:
Simply enter your query in the space provided, ensure that the Search word(s) field and the Match option are set to your requirements, and submit the form.
Exactly what you should put in the search field, or what the most appropriate option settings are, is discussed at appropriate points in the rest of this document. But first you should understand the mechanics of using forms.
The search form has three types of interaction:
an empty box is provided near the top of the form where you are expected to type your query. To do this, click on the box to activate it and type your text. When finished, DO NOT press <ENTER> as this will submit your query before you've had a chance to complete the rest of the form! Instead, use the mouse to position the cursor to whatever part of the form you want to work with next.
these are boxes (or paired square brackets) which display a value - the default setting. Other settings are available and can be viewed by selecting the "down arrow" button. To select an option, move the cursor to the desired item and press the left mouse button. The option list will close, and the newly selected value appears in the scroll box.
buttons or highlighted text are used to initiate an action. Positioning the cursor on the button and pressing the left mouse button will cause the action (indicated by the label) to occur. For instance, clicking on the "Submit" button will cause the form to be processed using whatever values you have input/selected.
The first part of the form prompts you to enter a query. The simplest query is one in which you type a single word. This word is then matched against an index. Remember that almost every word on a page is indexed, so try and choose a word or words that will be fairly specific to the area of interest. For instance, the word satellite alone will exist on a great many pages. Such words are so common that you should not use them in simple queries.
If matches for your query are found, a list of those pages corresponding to the index entry will be displayed.
At present the search facility performs an exact matching of words, if you search for orbit then a page containing only the plural, orbits, will not be found. However, there is a simple way around this, as the next section describes.
Searching on More than One Word
The present software version only allows for searching on words, rather than complete phrases. For example, if you enter phrase Research in Orbital Mechanics, then the search facility will return all pages containing all three words research, orbital and mechanics in any order. (Not in though, because it is a two-letter common word and not indexed.) In many cases, however, this is sufficient to find the relevant pages.
Note that if the Match option is set to "Any", then the search facility will return a list of pages which contain any of the words entered in the Search word(s) text box. This is useful when you have two or more alternative words to search for.
A general search on a substring, which is for all words containing a given string, is not permitted, but it is possible to search for all words starting with a given string. For example a search for telep* would search for pages containing telephone, telephones, teleprinter, etc. but *elep* would fail.
Two or more search terms (words) can be combined in a single query using Boolean logic. Used with care, this is a very powerful technique for improving the search result. Boolean queries involve combining terms using the special logical operators OR, AND, NOT, and parentheses.
The Match option must be set to "Boolean", and a valid Boolean expression must be entered in the Search word(s) textbox. For example:
will search for and list those pages that contain the word cat and do NOT contain the word dog.
searches for and lists those pages which contain the word tea, and either or both the words milk and cream, but exclude those pages which also contain the word sugar.
The Format scroll box provides the option of displaying additional information on the pages listed. If "Long" is selected then the pages of search results that are returned will show some text from each page listed. This may help in seeing whether a page is indeed relevant. The text will be either the contents of the <META name="description" content="contents"> mark-up in the page header if it exists, or an extract of text containing the search word, or the starting text of the page.
Scores and the "Sort by" Option
Pages are given a "score" by the search program according to how often a search word occurs, and also where it occurs: a word in a title will score higher than a word in the text of a document. The score of each page is indicated by one to five stars. Generally, a higher-scoring page is more likely to be relevant to the enquirer and so high scoring pages are shown first.
The "Sort by" scroll box gives the option of listing the pages that have been found in alphabetical order of title, or in order of the date they were created or last modified.
The present index is restricted to pages on AMSAT-UK and AMSAT-NA web sites, amsat-bb and sarex mailing lists from 1998.
At present the search facility will return up to ten pages of lists, each containing links to ten pages, this sets a limit of seeing one hundred pages however many may have been found.
Version 3.1.5 of ht://Dig does not permit the following: