[xwiki-users] rounding error in TagCloud - xwiki-users@xwiki.org

8 Feb 2011

Hey all,

the TagCloud macro has a rounding error. 

The result is, that the highest occurrence has no value in class attribute and is
displayed similar to notPopular.

The following code should solve the problem:

{{velocity}}

## 

## tagCloudSpace - the space to display the tag cloud for. If blank, display cloud for the
whole wiki. Default is blank.

#set ($tagCloudSpace = $context.macro.params.get('space'))

##

## Configurable popularity levels. You must an even number of levels. Default: 6.

#set ($popularityLevels = ["notPopular", "notVeryPopular",
"somewhatPopular", "popular", "veryPopular",
"ultraPopular"])

#set ($levelsHalf = $popularityLevels.size() / 2)

##

$xwiki.ssx.use("XWiki.TagCloud")

##

## Get tag count map. Key: tag, value: number of occurrences.

#set ($tagCount = $xwiki.tag.getTagCount("$!tagCloudSpace"))

##

## only build popularity map if at least one tag exists

#if ($tagCount.size() > 0)

  ##

  ## Store the minimum and maximum number of occurrences.

  #set ($sortedTagCounts = $sorttool.sort($tagCount.values()))

  #set ($maxIndex = $sortedTagCounts.size() - 1)

  #set ($minCount = $listtool.get($sortedTagCounts, 0))

  #set ($maxCount = $listtool.get($sortedTagCounts, $maxIndex))

  ##

  ## Calculate the total number of tags in the wiki.

  #set ($totalTagNumber = 0)

  #foreach ($currentTagCount in $sortedTagCounts)

    #set ($totalTagNumber = $totalTagNumber + $currentTagCount)

  #end

  #set ($countAverage = $mathtool.div($totalTagNumber, $tagCount.size()))

  ##

  ## Build popularity map using the difference between minimum maximum tag occurrences
counts

  ## and the average tag occurences count.

  #set ($firstHalfIntervalSize = $mathtool.div($mathtool.sub($countAverage, $minCount),
$levelsHalf))

  #set ($secondHalfIntervalSize = $mathtool.div($mathtool.sub($maxCount, $countAverage),
$levelsHalf))

  ##

  ## use a sorted map

  #set ($popularityMap = $util.getTreeMap())

  #set ($previousPopularityMax = $minCount)

  #set ($intervalSize = $firstHalfIntervalSize)

  #set ($halfPassed = false)

  #foreach ($popularityLevel in $popularityLevels)

    #if ($velocityCount > $levelsHalf && !$halfPassed)

      #set ($intervalSize = $secondHalfIntervalSize)

      #set ($halfPassed = true)

    #end

    #set ($currentPopularityMax = $mathtool.add($previousPopularityMax, $intervalSize))

    ##

    ## round the threshold

    #set ($threshold = $mathtool.roundTo(1, $currentPopularityMax))

    #set ($discard = $popularityMap.put($threshold, $popularityLevel))

    #set ($previousPopularityMax = $currentPopularityMax)

  #end

#end

##

## Display tag cloud.

{{html}}

#if ($tagCount.size() > 0)

  <ol class="tagCloud">

  #foreach ($tagEntry in $tagCount.entrySet())

    #foreach ($popularityEntry in $popularityMap.entrySet())

      #if ($popularityEntry.Key >= $tagEntry.Value)

        #set ($liClass = $popularityEntry.Value)

        #break

      #end

    #end

    <li class="$liClass">

      <a class="tag" href="$xwiki.getURL("Main.Tags",
"view", "do=viewTag&amp;tag=$escapetool.url($tagEntry.Key)")"
title="$msg.get("xe.tag.tooltip",
["$tagEntry.Value"])">$escapetool.xml($tagEntry.Key)</a>

    </li>

  #end

  </ol>

#else

  #if("$!tagCloudSpace" == "")

    $msg.get("xe.tag.notags")

  #else

    $msg.get("xe.tag.notagsforspace", ["$tagCloudSpace"])

  #end

#end

{{/html}}

{{/velocity}}

best regards

  Jörg