diff --git a/HISTORY.md b/HISTORY.md
index 3295b451..24f9a9ba 100755
--- a/HISTORY.md
+++ b/HISTORY.md
@@ -4,6 +4,7 @@
 ### 2018-10-23
 * Objects: Don't stamp if the canvas is too small (and would throw an error)
 * Threads: New "reportAtomicGroup" HOF primitive using the JIT compiler
+* "Bigger Data" library: Added "group" function for fast data drill-down analyses
 
 ### 2018-10-22
 * "Bigger Data" library: Added "analyze" function for fast frequency distributions
diff --git a/libraries/atomic_HOFs_module.xml b/libraries/atomic_HOFs_module.xml
index 2073641c..0dc4e3fc 100644
--- a/libraries/atomic_HOFs_module.xml
+++ b/libraries/atomic_HOFs_module.xml
@@ -1 +1 @@
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+<blocks app="Snap! 4.2, http://snap.berkeley.edu" version="1"><block-definition s="$flash map %&apos;fn&apos; over %&apos;data&apos;" type="reporter" category="lists"><header></header><code></code><translations></translations><inputs><input type="%repRing"></input><input type="%l"></input></inputs><script><block s="doReport"><block s="evaluate"><block s="reportJSFunction"><list><l>fn</l><l>data</l><l>proc</l></list><l>return proc.reportAtomicMap(fn, data);</l></block><list><block var="fn"/><block var="data"/></list></block></block></script></block-definition><block-definition s="$flash keep %&apos;test&apos; from %&apos;data&apos;" type="reporter" category="lists"><header></header><code></code><translations></translations><inputs><input type="%predRing"></input><input type="%l"></input></inputs><script><block s="doReport"><block s="evaluate"><block s="reportJSFunction"><list><l>fn</l><l>data</l><l>proc</l></list><l>return proc.reportAtomicKeep(fn, data);</l></block><list><block var="test"/><block var="data"/></list></block></block></script></block-definition><block-definition s="$flash combine %&apos;fn&apos; with %&apos;data&apos;" type="reporter" category="lists"><header></header><code></code><translations></translations><inputs><input type="%repRing"></input><input type="%l"></input></inputs><script><block s="doReport"><block s="evaluate"><block s="reportJSFunction"><list><l>fn</l><l>data</l><l>proc</l></list><l>return proc.reportAtomicCombine(fn, data);</l></block><list><block var="fn"/><block var="data"/></list></block></block></script></block-definition><block-definition s="$flash sort %&apos;data&apos; by %&apos;fn&apos;" type="reporter" category="lists"><header></header><code></code><translations></translations><inputs><input type="%l"></input><input type="%predRing"></input></inputs><script><block s="doReport"><block s="evaluate"><block s="reportJSFunction"><list><l>data</l><l>fn</l><l>proc</l></list><l>return proc.reportAtomicSort(data, fn);</l></block><list><block var="data"/><block var="fn"/></list></block></block></script></block-definition><block-definition s="$flash reverse %&apos;list&apos;" type="reporter" category="lists"><header></header><code></code><translations></translations><inputs><input type="%l"></input></inputs><script><block s="doReport"><block s="evaluate"><block s="reportJSFunction"><list><l>list</l></list><l>return new List(list.asArray().slice().reverse());</l></block><list><block var="list"/></list></block></block></script></block-definition><block-definition s="$flash analyze %&apos;data&apos;" type="reporter" category="lists"><comment x="0" y="0" w="149" collapsed="false">returns a frequency analysis of the argument list, represented as a two-column table, where the first column contains the unique values and the second column their occurrences</comment><header></header><code></code><translations></translations><inputs><input type="%l"></input></inputs><script><block s="doReport"><block s="evaluate"><block s="reportJSFunction"><list><l>list</l></list><l>var dict = new Map(),&#xD;    result = [],&#xD;    data = list.asArray(),&#xD;    len = data.length,&#xD;    i;&#xD;for (i = 0; i &lt; len; i += 1) {&#xD;    if (dict.has(data[i])) {&#xD;        dict.set(data[i], dict.get(data[i]) + 1);&#xD;    } else {&#xD;        dict.set(data[i], 1);&#xD;    }&#xD;}&#xD;dict.forEach(function (value, key) {&#xD;    result.push(new List([key, value]));&#xD;});&#xD;return new List(result);</l></block><list><block var="data"/></list></block></block></script></block-definition><block-definition s="$flash group %&apos;data&apos; by %&apos;fn&apos;" type="reporter" category="lists"><header></header><code></code><translations></translations><inputs><input type="%l"></input><input type="%repRing"></input></inputs><script><block s="doReport"><block s="evaluate"><block s="reportJSFunction"><list><l>data</l><l>fn</l><l>proc</l></list><l>return proc.reportAtomicGroup(data, fn);</l></block><list><block var="data"/><block var="fn"/></list></block></block></script></block-definition></blocks>
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