M [F N]
</literallayout>
where M is an integer, used as a
- multiplier against the basic TF*IDF score. A value of
+ weight against the basic TF*IDF score. A value of
1 is the base, higher values give additional weight to
elements of this type. The default is '0', which
excludes this element from the rank calculation.
The per field rank was introduced in Pazpar2 1.6.15. Earlier
releases only allowed a rank value M (simple integer).
</para>
+ See <xref linkend="relevance_ranking"/> for more
+ about ranking.
</listitem>
</varlistentry>
all elements), or 'no' (don't merge; this is the
default);
</para>
+ <para>
+ Pazpar 1.6.24 also offers a new value for merge, 'first', which
+ is like 'all' but only takes all from first database that returns
+ the particular metadata field.
+ </para>
</listitem>
</varlistentry>
</varlistentry>
<varlistentry>
+ <term id="limitcluster">limitcluster</term>
+ <listitem>
+ <para>
+ Allow a limit on merged metadata. The value of this attribute
+ is the name of actual metadata content to be used for matching
+ (most often same name as metadata name).
+ </para>
+ <note>
+ <para>
+ Requires Pazpar2 1.6.23 or later.
+ </para>
+ </note>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
<term id="metadata_limitmap">limitmap</term>
<listitem>
<para>
<term>rank</term>
<listitem>
<para>
- Customizes the ranking (relevance) algorithm.
- Attribute 'cluster' is a boolean
- that controls whether Pazpar2 should boost ranking for merged
- records. Is 'yes' by default. A value of 'no' will make
- Pazpar2 avergage ranking of each record in a cluster.
+ Customizes the ranking (relevance) algorithm. Also known as
+ rank tweaks. The rank element
+ accepts the following attributes - all being optional:
</para>
+ <variablelist>
+ <varlistentry>
+ <term>cluster</term>
+ <listitem>
+ <para>
+ Attribute 'cluster' is a boolean
+ that controls whether Pazpar2 should boost ranking for merged
+ records. Is 'yes' by default. A value of 'no' will make
+ Pazpar2 average ranking of each record in a cluster.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>debug</term>
+ <listitem>
+ <para>
+ Attribute 'debug' is a boolean
+ that controls whether Pazpar2 should include details
+ about ranking for each document in the show command's
+ response. Enable by using value "yes", disable by using
+ value "no" (default).
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>follow</term>
+ <listitem>
+ <para>
+ Attribute 'follow' is a a floating point number greater than
+ or equal to 0. A positive number will boost weight for terms
+ that occur close to each other (proximity, distance).
+ A value of 1, will double the weight if two terms are in
+ proximity distance of 1 (next to each other). The default
+ value of 'follow' is 0 (order will not affect weight).
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>lead</term>
+ <listitem>
+ <para>
+ Attribute 'lead' is a floating point number.
+ It controls if term weight should be reduced by position
+ from start in a metadata field. A positive value of 'lead'
+ will reduce weight as it apperas further away from the lead
+ of the field. Default value is 0 (no reduction of weight by
+ position).
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>length</term>
+ <listitem>
+ <para>
+ Attribute 'length' determines how/if term weight should be
+ divided by lenght of metadata field. A value of "linear"
+ divide by length. A value of "log" will divide by log2(length).
+ A value of "none" will leave term weight as is (no division).
+ Default value is "linear".
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
<para>
- This configuration was added in pazpar2 1.6.18.
+ Refer to <xref linkend="relevance_ranking"/> to see how
+ these tweaks are used in computation of score.
+ </para>
+ <para>
+ Customization of ranking algorithm was introduced with
+ Pazpar2 1.6.18. The semantics of some of the fields changed
+ in versions up to 1.6.22.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry id="sort-default">
+ <term>sort-default</term>
+ <listitem>
+ <para>
+ Specifies the default sort criteria (default 'relevance'),
+ which previous was hard-coded as default criteria in search.
+ This is a fix/work-around to avoid re-searching when using
+ target-based sorting. In order for this to work efficient,
+ the search must also have the sort critera parameter; otherwise
+ pazpar2 will do re-searching on search criteria changes, if
+ changed between search and show command.
+ </para>
+ <para>
+ This configuration was added in pazpar2 1.6.20.
</para>
</listitem>
</varlistentry>
</listitem>
</varlistentry>
<varlistentry>
+ <term>pz:extendrecs</term>
+ <listitem>
+ <para>
+ If a show command goes to the boundary of a result set for a
+ database - depends on sorting - and pz:extendrecs is set to a larger
+ value of pz:maxrecs, then Pazpar2 wait for show to fetch remaining
+ records - up to pz:extendrecs. This setting is best used if a
+ database does native sorting, because the result set otherwise may
+ be completely re-sorted during extended fetch.
+ </para>
+ <note>
+ <para>
+ The pz:extendrecs setting is supported in Pazpar2 version 1.6.26.
+ </para>
+ </note>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
<term>pz:presentchunk</term>
<listitem>
<para>
by a field a metadata field (default is to use the name of the
limitmap itself).
</para>
+ <para>
+ For Pazpar2 version 1.6.23 and later the limitmap may include multiple
+ specifications, separated by <literal>,</literal> (comma).
+ For example:
+ <literal>ccl:title,local:ltitle,rpn:@attr 1=4</literal>.
+ </para>
<note>
<para>
The limitmap facility is supported for Pazpar2 version 1.6.0.
projects / pazpar2-moved-to-github.git / blobdiff