1 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
4 <META NAME="GENERATOR" CONTENT="SGML-Tools 1.0.9">
5 <TITLE>The DXSpider User Manual : Filtering (From version 1.45)</TITLE>
6 <LINK HREF="usermanual-11.html" REL=next>
7 <LINK HREF="usermanual-9.html" REL=previous>
8 <LINK HREF="usermanual.html#toc10" REL=contents>
9 <link rel=stylesheet href="style.css" type="text/css" title="default stylesheet">
12 <A HREF="usermanual-11.html">Next</A>
13 <A HREF="usermanual-9.html">Previous</A>
14 <A HREF="usermanual.html#toc10">Contents</A>
16 <H2><A NAME="s10">10. Filtering (From version 1.45)</A></H2>
18 <H2><A NAME="ss10.1">10.1 General filter rules</A>
21 <P>Upto v1.44 it was not possible for the user to set their own filters. From
22 v1.45 though that has all changed. It is now possible to set filters for just
23 about anything you wish. If you have just updated from an older version of
24 DXSpider you will need to update your new filters. You do not need to do
25 anything with your old filters, they will be renamed as you update.
27 <P>There are 3 basic commands involved in setting and manipulating filters. These
28 are <EM>accept</EM>, <EM>reject</EM> and <EM>clear</EM>. First we will look
29 generally at filtering. There are a number of things you can filter in the
30 DXSpider system. They all use the same general mechanism.
32 <P>In general terms you can create a 'reject' or an 'accept' filter which can have
33 up to 10 lines in it. You do this using, for example ...
42 <P>where ..... are the specific commands for that type of filter. There are
43 filters for spots, wwv, announce, wcy and (for sysops) connects. See each
44 different accept or reject command reference for more details.
45 <P>There is also a command to clear out one or more lines in a filter. They are ...
53 <P>There is clear/xxxx command for each type of filter.
55 <P>and you can check that your filters have worked by the command ...
64 <P>For now we are going to use spots for the examples, but you can apply the same
65 principles to all types of filter.
67 <H2><A NAME="ss10.2">10.2 Types of filter</A>
70 <P>There are two main types of filter, <EM>accept</EM> or <EM>reject</EM>. You
71 can use either to achieve the result you want dependent on your own preference
72 and which is more simple to do. It is pointless writing 8 lines of reject
73 filters when 1 accept filter would do the same thing! Each filter has 10
74 lines (of any length) which are tried in order. If a line matches then the
75 action you have specified is taken (ie reject means ignore it and accept
78 <P>If you specify reject filters, then any lines that arrive that match the filter
79 will be dumped but all else will be accepted. If you use an accept filter,
80 then ONLY the lines in the filter will be accepted and all else will be dumped.
81 For example if you have a single line <EM>accept</EM> filter ...
85 accept/spots on vhf and (by_zone 14,15,16 or call_zone 14,15,16)
88 <P>then you will <EM>ONLY</EM> get VHF spots <EM>from</EM> or <EM>to</EM> CQ zones
91 <P>If you set a reject filter like this ...
98 <P>Then you will get everything <EM>EXCEPT</EM> HF CW spots. You could make this
99 single filter even more flexible. For example, if you are interested in IOTA
100 and will work it even on CW even though normally you are not interested in
101 CW, then you could say ...
105 reject/spots on hf/cw and not info iota
108 <P>But in that case you might only be interested in iota and say:-
112 accept/spots not on hf/cw or info iota
115 <P>which achieves exactly the same thing. You should choose one or the other
116 until you are comfortable with the way it works. You can mix them if you
117 wish (actually you can have an accept AND a reject on the same line) but
118 don't attempt this until you are sure you know what you are doing!
120 <P>You can arrange your filter lines into logical units, either for your own
121 understanding or simply convenience. Here is an example ...
125 reject/spots 1 on hf/cw
126 reject/spots 2 on 50000/1400000 not (by_zone 14,15,16 or call_zone 14,15,16)
129 <P>What this does is to ignore all HF CW spots and also rejects any spots on VHF
130 which don't either originate or spot someone in Europe.
132 <P>This is an example where you would use a line number (1 and 2 in this case), if
133 you leave the digit out, the system assumes '1'. Digits '0'-'9' are available.
134 This make it easier to see just what filters you have set. It also makes it
135 more simple to remove individual filters, during a contest for example.
137 <P>You will notice in the above example that the second line has brackets. Look
138 at the line logically. You can see there are 2 separate sections to it. We
139 are saying reject spots that are VHF or above <EM>APART</EM> from those in
140 zones 14, 15 and 16 (either spotted there or originated there). If you did
141 not have the brackets to separate the 2 sections, then Spider would read it
142 logically from the front and see a different expression entirely ...
146 (on 50000/1400000 and by_zone 14,15,16) or call_zone 14,15,16
149 <P>The simple way to remember this is, if you use OR - use brackets. Whilst we are
150 here CASE is not important. 'And BY_Zone' is just the same as 'and by_zone'.
151 <P>As mentioned earlier, setting several filters can be more flexible than
152 simply setting one complex one. Doing it in this way means that if you want
153 to alter your filter you can just redefine or remove one or more lines of it or
154 one line. For example ...
158 reject/spots 1 on hf/ssb
161 <P>would redefine our earlier example, or
168 <P>To remove all the filter lines in the spot filter ...
176 <H2><A NAME="ss10.3">10.3 Filter options</A>
179 <P>You can filter in several different ways. The options are listed in the
180 various helpfiles for accept, reject and filter.
182 <H2><A NAME="ss10.4">10.4 Advanced filtering</A>
185 <P>Once you are happy with the results you get, you may like to experiment.
187 <P>The previous example that filters hf/cw spots and accepts vhf/uhf spots from EU
188 can be written with a mixed filter, for example ...
194 acc/spot 2 on 50000/1400000 and (by_zone 14,15,16 or call_zone 14,15,16)
197 <P>Note that the first filter has not been specified with a number. This
198 will automatically be assumed to be number 1. In this case, we have
199 said <EM>reject all HF spots in the CW section of the bands but accept
200 all others at HF. Also accept anything in VHF and above spotted in or
201 by operators in the zones 14, 15 and 16</EM>. Each filter slot actually
202 has a 'reject' slot and an 'accept' slot. The reject slot is executed
203 BEFORE the accept slot.
205 <P>It was mentioned earlier that after a reject test that doesn't match, the
206 default for following tests is 'accept', the reverse is true for 'accept'.
207 In the example what happens is that the reject is executed first, any non
208 hf/cw spot is passed to the accept line, which lets through everything
209 else on HF. The next filter line lets through just VHF/UHF spots from EU.
213 <A HREF="usermanual-11.html">Next</A>
214 <A HREF="usermanual-9.html">Previous</A>
215 <A HREF="usermanual.html#toc10">Contents</A>