91 lines
3.9 KiB
XML
91 lines
3.9 KiB
XML
<?xml version="1.0" encoding="ISO-8859-1"?>
|
|
<package xmlns="http://www.lovullo.com/rater"
|
|
xmlns:c="http://www.lovullo.com/calc"
|
|
xmlns:t="http://www.lovullo.com/rater/apply-template"
|
|
core="true"
|
|
desc="Matrix (vector of vectors) arithmetic">
|
|
|
|
<import package="../base" />
|
|
<import package="list" />
|
|
|
|
|
|
<!--
|
|
Extracts a vector of rates (a value for each location) associated with the
|
|
requested class and line codes
|
|
|
|
This seems more complicated/confusing than it really is, so it helps to
|
|
look at an example. Consider that we have the following data passed to this
|
|
template (assuming that this is the data that will exist at runtime):
|
|
|
|
R = [ [ "A", "B" ], [ "C" ], [ "D", "E" ] ]
|
|
C = [ [ 1 , 0 ], [ 0 ], [ 0, 1 ] ]
|
|
L = "gl"
|
|
|
|
Given matrix R (@rate_matrix@) and the classification matches C, for any
|
|
index that matches the given line L, a dot product will be performed. Let
|
|
us assume that indexes 0 and 2 match GL; we would then have the following
|
|
dot product:
|
|
|
|
R = [ [ "A", "B" ], ..., [ "D", "E" ] ]
|
|
C = [ [ 1 , 0 ], ..., [ 0, 1 ] ]
|
|
= [ "A", "E" ]
|
|
|
|
And so the resulting vector would be [ "A", "E" ]. To put this into an
|
|
example within the context of dwelling, let C above be the classification
|
|
set for all vacant buildings. Then, [ "A", "E" ] would be the rate
|
|
associated with the vacant building class code for locations 0 and 2
|
|
respectively.
|
|
|
|
If multiple matches are found per location, then the two rates will be
|
|
summed (as that is how dot products work), which is obviously not good.
|
|
However, this should not be a problem, because you should not have
|
|
duplicate class codes per location. Fix your data if that happens.
|
|
|
|
(Note that the dot product is actually performed for each index and then
|
|
multiplied by the classification match __CMATCH__, so while the effect
|
|
above is true, the result is achieved in a slightly different manner.)
|
|
-->
|
|
<!-- TODO: more generic name and documentation; we are in the core, after all -->
|
|
<template name="_rate-vector_" desc="Matches against a matrix of classes and a matrix of rates and returns a vector representing the rates per location">
|
|
<param name="@line@" desc="Line code classification string" />
|
|
<param name="@class_set@" desc="Matrix containing line classification matches" />
|
|
<param name="@into@" desc="Variable to which the vector will be assigned" />
|
|
|
|
<!-- this would be the sum of all the rates, which really is useless, but the XML requires it -->
|
|
<param name="@yields@" desc="Variable to yield to (useless, but required)">
|
|
<text>__</text>
|
|
<param-value name="@into@" />
|
|
</param>
|
|
|
|
<param name="@rate_matrix@" desc="Matrix containing the rates for the given line">
|
|
<text>rate_</text>
|
|
<param-value name="@line@" />
|
|
</param>
|
|
|
|
<rate-each class="@line@" accumulate="none" yields="@yields@" generates="@into@" index="k">
|
|
<!-- take the dot product of the two vectors (each part of a larger matrix)
|
|
to get the rate for the associated class code -->
|
|
<c:product dot="true" label="Dot product between the class and rate vectors for each location will yield the respective rate per location">
|
|
<c:value-of name="@class_set@" index="k" />
|
|
<c:value-of name="@rate_matrix@" index="k" />
|
|
</c:product>
|
|
</rate-each>
|
|
</template>
|
|
|
|
|
|
<function name="mcol" desc="Retrieve a matrix column as a vector">
|
|
<param name="matrix" type="float" set="matrix" desc="Matrix" />
|
|
<param name="col" type="integer" desc="Column index (0-indexed)" />
|
|
|
|
<!-- generate a vector containing only the requested column from each row -->
|
|
<t:cons-until-empty set="matrix" car="row">
|
|
<c:value-of name="row">
|
|
<c:index>
|
|
<c:value-of name="col" />
|
|
</c:index>
|
|
</c:value-of>
|
|
</t:cons-until-empty>
|
|
</function>
|
|
</package>
|
|
|