groupBy.html

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<ul>
<li id="page-tree" class="folder">
<ul>
<li><a href="./getting-started" title="Getting Started">Getting Started</a></li>
<li><a href="./custom-builds" title="Custom Builds">Custom Builds</a></li>
<li><a href="./all" title="All-in-one Doc">All-in-one Doc</a></li>
</ul></li>
<li id="page-tree-array" class="folder"><span class="folderPage">Array</span>
<ul>
<li><a href="./chunk" title="_.chunk(array, [size=0])">chunk</a></li>
<li><a href="./compact" title="_.compact(array)">compact</a></li>
<li><a href="./concat" title="_.concat(array, [values])">concat</a></li>
<li><a href="./difference" title="_.difference(array, [values])">difference</a></li>
<li><a href="./differenceBy" title="_.differenceBy(array, [values], [iteratee=_.identity])">differenceBy</a></li>
<li><a href="./differenceWith" title="_.differenceWith(array, [values], [comparator])">differenceWith</a></li>
<li><a href="./drop" title="_.drop(array, [n=1])">drop</a></li>
<li><a href="./dropRight" title="_.dropRight(array, [n=1])">dropRight</a></li>
<li><a href="./dropRightWhile" title="_.dropRightWhile(array, [predicate=_.identity])">dropRightWhile</a></li>
<li><a href="./dropWhile" title="_.dropWhile(array, [predicate=_.identity])">dropWhile</a></li>
<li><a href="./fill" title="_.fill(array, value, [start=0], [end=array.length])">fill</a></li>
<li><a href="./findIndex" title="_.findIndex(array, [predicate=_.identity])">findIndex</a></li>
<li><a href="./findLastIndex" title="_.findLastIndex(array, [predicate=_.identity])">findLastIndex</a></li>
<li><a href="./flatten" title="_.flatten(array)">flatten</a></li>
<li><a href="./flattenDeep" title="_.flattenDeep(array)">flattenDeep</a></li>
<li><a href="./flattenDepth" title="_.flattenDepth(array, [depth=1])">flattenDepth</a></li>
<li><a href="./fromPairs" title="_.fromPairs(pairs)">fromPairs</a></li>
<li><a href="./head" title="_.head(array)">head <span class="aliases">first</span></a></li>
<li><a href="./indexOf" title="_.indexOf(array, value, [fromIndex=0])">indexOf</a></li>
<li><a href="./initial" title="_.initial()">initial</a></li>
<li><a href="./intersection" title="_.intersection([arrays])">intersection</a></li>
<li><a href="./intersectionBy" title="_.intersectionBy([arrays], [iteratee=_.identity])">intersectionBy</a></li>
<li><a href="./intersectionWith" title="_.intersectionWith([arrays], [comparator])">intersectionWith</a></li>
<li><a href="./join" title="_.join(array, [separator=&#39;,&#39;])">join</a></li>
<li><a href="./last" title="_.last(array)">last</a></li>
<li><a href="./lastIndexOf" title="_.lastIndexOf(array, value, [fromIndex=array.length-1])">lastIndexOf</a></li>
<li><a href="./prototype-reverse" title="_.prototype.reverse()">prototype.reverse</a></li>
<li><a href="./pull" title="_.pull(array, [values])">pull</a></li>
<li><a href="./pullAll" title="_.pullAll(array, values)">pullAll</a></li>
<li><a href="./pullAllBy" title="_.pullAllBy(array, values, [iteratee=_.identity])">pullAllBy</a></li>
<li><a href="./pullAt" title="_.pullAt(array, [indexes])">pullAt</a></li>
<li><a href="./remove" title="_.remove(array, [predicate=_.identity])">remove</a></li>
<li><a href="./slice" title="_.slice(array, [start=0], [end=array.length])">slice</a></li>
<li><a href="./sortedIndex" title="_.sortedIndex(array, value)">sortedIndex</a></li>
<li><a href="./sortedIndexBy" title="_.sortedIndexBy(array, value, [iteratee=_.identity])">sortedIndexBy</a></li>
<li><a href="./sortedIndexOf" title="_.sortedIndexOf(array, value)">sortedIndexOf</a></li>
<li><a href="./sortedLastIndex" title="_.sortedLastIndex(array, value)">sortedLastIndex</a></li>
<li><a href="./sortedLastIndexBy" title="_.sortedLastIndexBy(array, value, [iteratee=_.identity])">sortedLastIndexBy</a></li>
<li><a href="./sortedLastIndexOf" title="_.sortedLastIndexOf(array, value)">sortedLastIndexOf</a></li>
<li><a href="./sortedUniq" title="_.sortedUniq(array)">sortedUniq</a></li>
<li><a href="./sortedUniqBy" title="_.sortedUniqBy(array, [iteratee])">sortedUniqBy</a></li>
<li><a href="./tail" title="_.tail(array)">tail</a></li>
<li><a href="./take" title="_.take(array, [n=1])">take</a></li>
<li><a href="./takeRight" title="_.takeRight(array, [n=1])">takeRight</a></li>
<li><a href="./takeRightWhile" title="_.takeRightWhile(array, [predicate=_.identity])">takeRightWhile</a></li>
<li><a href="./takeWhile" title="_.takeWhile(array, [predicate=_.identity])">takeWhile</a></li>
<li><a href="./union" title="_.union([arrays])">union</a></li>
<li><a href="./unionBy" title="_.unionBy([arrays], [iteratee=_.identity])">unionBy</a></li>
<li><a href="./unionWith" title="_.unionWith([arrays], [comparator])">unionWith</a></li>
<li><a href="./uniq" title="_.uniq(array)">uniq</a></li>
<li><a href="./uniqBy" title="_.uniqBy(array, [iteratee=_.identity])">uniqBy</a></li>
<li><a href="./uniqWith" title="_.uniqWith(array, [comparator])">uniqWith</a></li>
<li><a href="./unzip" title="_.unzip(array)">unzip</a></li>
<li><a href="./unzipWith" title="_.unzipWith(array, [iteratee=_.identity])">unzipWith</a></li>
<li><a href="./without" title="_.without(array, [values])">without</a></li>
<li><a href="./xor" title="_.xor([arrays])">xor</a></li>
<li><a href="./xorBy" title="_.xorBy([arrays], [iteratee=_.identity])">xorBy</a></li>
<li><a href="./xorWith" title="_.xorWith([arrays], [comparator])">xorWith</a></li>
<li><a href="./zip" title="_.zip([arrays])">zip</a></li>
<li><a href="./zipObject" title="_.zipObject([props=[]], [values=[]])">zipObject</a></li>
<li><a href="./zipObjectDeep" title="_.zipObjectDeep([props=[]], [values=[]])">zipObjectDeep</a></li>
<li><a href="./zipWith" title="_.zipWith([arrays])">zipWith</a></li>
</ul></li>
<li id="page-tree-collection" class="folder"><span class="folderPage">Collection</span>
<ul>
<li><a href="./countBy" title="_.countBy(collection, [iteratee=_.identity])">countBy</a></li>
<li><a href="./every" title="_.every(collection, [predicate=_.identity])">every</a></li>
<li><a href="./filter" title="_.filter(collection, [predicate=_.identity])">filter</a></li>
<li><a href="./find" title="_.find(collection, [predicate=_.identity])">find</a></li>
<li><a href="./findLast" title="_.findLast(collection, [predicate=_.identity])">findLast</a></li>
<li><a href="./flatMap" title="_.flatMap(collection, [iteratee=_.identity])">flatMap</a></li>
<li><a href="./forEach" title="_.forEach(collection, [iteratee=_.identity])">forEach <span class="aliases">each</span></a></li>
<li><a href="./forEachRight" title="_.forEachRight(collection, [iteratee=_.identity])">forEachRight <span class="aliases">eachRight</span></a></li>
<li><a href="./groupBy" title="_.groupBy(collection, [iteratee=_.identity])" class = "open">groupBy</a></li>
<li><a href="./includes" title="_.includes(collection, value, [fromIndex=0])">includes</a></li>
<li><a href="./invokeMap" title="_.invokeMap(collection, path, [args])">invokeMap</a></li>
<li><a href="./keyBy" title="_.keyBy(collection, [iteratee=_.identity])">keyBy</a></li>
<li><a href="./map" title="_.map(collection, [iteratee=_.identity])">map</a></li>
<li><a href="./orderBy" title="_.orderBy(collection, [iteratees=[_.identity]], [orders])">orderBy</a></li>
<li><a href="./partition" title="_.partition(collection, [predicate=_.identity])">partition</a></li>
<li><a href="./reduce" title="_.reduce(collection, [iteratee=_.identity], [accumulator])">reduce</a></li>
<li><a href="./reduceRight" title="_.reduceRight(collection, [iteratee=_.identity], [accumulator])">reduceRight</a></li>
<li><a href="./reject" title="_.reject(collection, [predicate=_.identity])">reject</a></li>
<li><a href="./sample" title="_.sample(collection)">sample</a></li>
<li><a href="./sampleSize" title="_.sampleSize(collection, [n=0])">sampleSize</a></li>
<li><a href="./shuffle" title="_.shuffle(collection)">shuffle</a></li>
<li><a href="./size" title="_.size(collection)">size</a></li>
<li><a href="./some" title="_.some(collection, [predicate=_.identity])">some</a></li>
<li><a href="./sortBy" title="_.sortBy(collection, [iteratees=[_.identity]])">sortBy</a></li>
</ul></li>
<li id="page-tree-date" class="folder"><span class="folderPage">Date</span>
<ul>
<li><a href="./now" title="_.now()">now</a></li>
</ul></li>
<li id="page-tree-function" class="folder"><span class="folderPage">Function</span>
<ul>
<li><a href="./after" title="_.after(n, func)">after</a></li>
<li><a href="./ary" title="_.ary(func, [n=func.length])">ary</a></li>
<li><a href="./before" title="_.before(n, func)">before</a></li>
<li><a href="./bind" title="_.bind(func, thisArg, [partials])">bind</a></li>
<li><a href="./bindKey" title="_.bindKey(object, key, [partials])">bindKey</a></li>
<li><a href="./curry" title="_.curry(func, [arity=func.length])">curry</a></li>
<li><a href="./curryRight" title="_.curryRight(func, [arity=func.length])">curryRight</a></li>
<li><a href="./debounce" title="_.debounce(func, [wait=0], [options])">debounce</a></li>
<li><a href="./defer" title="_.defer(func, [args])">defer</a></li>
<li><a href="./delay" title="_.delay(func, wait, [args])">delay</a></li>
<li><a href="./flip" title="_.flip(func)">flip</a></li>
<li><a href="./memoize" title="_.memoize(func, [resolver])">memoize</a></li>
<li><a href="./negate" title="_.negate(predicate)">negate</a></li>
<li><a href="./once" title="_.once(func)">once</a></li>
<li><a href="./overArgs" title="_.overArgs(func, [transforms])">overArgs</a></li>
<li><a href="./partial" title="_.partial(func, [partials])">partial</a></li>
<li><a href="./partialRight" title="_.partialRight(func, [partials])">partialRight</a></li>
<li><a href="./rearg" title="_.rearg(func, indexes)">rearg</a></li>
<li><a href="./rest" title="_.rest(func, [start=func.length-1])">rest</a></li>
<li><a href="./spread" title="_.spread(func)">spread</a></li>
<li><a href="./throttle" title="_.throttle(func, [wait=0], [options])">throttle</a></li>
<li><a href="./unary" title="_.unary(func)">unary</a></li>
<li><a href="./wrap" title="_.wrap(value, wrapper)">wrap</a></li>
</ul></li>
<li id="page-tree-lang" class="folder"><span class="folderPage">Lang</span>
<ul>
<li><a href="./castArray" title="_.castArray(value)">castArray</a></li>
<li><a href="./clone" title="_.clone(value)">clone</a></li>
<li><a href="./cloneDeep" title="_.cloneDeep(value)">cloneDeep</a></li>
<li><a href="./cloneDeepWith" title="_.cloneDeepWith(value, [customizer])">cloneDeepWith</a></li>
<li><a href="./cloneWith" title="_.cloneWith(value, [customizer])">cloneWith</a></li>
<li><a href="./eq" title="_.eq(value, other)">eq</a></li>
<li><a href="./gt" title="_.gt(value, other)">gt</a></li>
<li><a href="./gte" title="_.gte(value, other)">gte</a></li>
<li><a href="./isArguments" title="_.isArguments(value)">isArguments</a></li>
<li><a href="./isArray" title="_.isArray(value)">isArray</a></li>
<li><a href="./isArrayBuffer" title="_.isArrayBuffer(value)">isArrayBuffer</a></li>
<li><a href="./isArrayLike" title="_.isArrayLike(value)">isArrayLike</a></li>
<li><a href="./isArrayLikeObject" title="_.isArrayLikeObject(value)">isArrayLikeObject</a></li>
<li><a href="./isBoolean" title="_.isBoolean(value)">isBoolean</a></li>
<li><a href="./isBuffer" title="_.isBuffer(value)">isBuffer</a></li>
<li><a href="./isDate" title="_.isDate(value)">isDate</a></li>
<li><a href="./isElement" title="_.isElement(value)">isElement</a></li>
<li><a href="./isEmpty" title="_.isEmpty(value)">isEmpty</a></li>
<li><a href="./isEqual" title="_.isEqual(value, other)">isEqual</a></li>
<li><a href="./isEqualWith" title="_.isEqualWith(value, other, [customizer])">isEqualWith</a></li>
<li><a href="./isError" title="_.isError(value)">isError</a></li>
<li><a href="./isFinite" title="_.isFinite(value)">isFinite</a></li>
<li><a href="./isFunction" title="_.isFunction(value)">isFunction</a></li>
<li><a href="./isInteger" title="_.isInteger(value)">isInteger</a></li>
<li><a href="./isLength" title="_.isLength(value)">isLength</a></li>
<li><a href="./isMap" title="_.isMap(value)">isMap</a></li>
<li><a href="./isMatch" title="_.isMatch(object, source)">isMatch</a></li>
<li><a href="./isMatchWith" title="_.isMatchWith(object, source, [customizer])">isMatchWith</a></li>
<li><a href="./isNaN" title="_.isNaN(value)">isNaN</a></li>
<li><a href="./isNative" title="_.isNative(value)">isNative</a></li>
<li><a href="./isNil" title="_.isNil(value)">isNil</a></li>
<li><a href="./isNull" title="_.isNull(value)">isNull</a></li>
<li><a href="./isNumber" title="_.isNumber(value)">isNumber</a></li>
<li><a href="./isObject" title="_.isObject(value)">isObject</a></li>
<li><a href="./isObjectLike" title="_.isObjectLike(value)">isObjectLike</a></li>
<li><a href="./isPlainObject" title="_.isPlainObject(value)">isPlainObject</a></li>
<li><a href="./isRegExp" title="_.isRegExp(value)">isRegExp</a></li>
<li><a href="./isSafeInteger" title="_.isSafeInteger(value)">isSafeInteger</a></li>
<li><a href="./isSet" title="_.isSet(value)">isSet</a></li>
<li><a href="./isString" title="_.isString(value)">isString</a></li>
<li><a href="./isSymbol" title="_.isSymbol(value)">isSymbol</a></li>
<li><a href="./isTypedArray" title="_.isTypedArray(value)">isTypedArray</a></li>
<li><a href="./isUndefined" title="_.isUndefined(value)">isUndefined</a></li>
<li><a href="./isWeakMap" title="_.isWeakMap(value)">isWeakMap</a></li>
<li><a href="./isWeakSet" title="_.isWeakSet(value)">isWeakSet</a></li>
<li><a href="./lt" title="_.lt(value, other)">lt</a></li>
<li><a href="./lte" title="_.lte(value, other)">lte</a></li>
<li><a href="./toArray" title="_.toArray(value)">toArray</a></li>
<li><a href="./toInteger" title="_.toInteger(value)">toInteger</a></li>
<li><a href="./toLength" title="_.toLength(value)">toLength</a></li>
<li><a href="./toNumber" title="_.toNumber(value)">toNumber</a></li>
<li><a href="./toPlainObject" title="_.toPlainObject(value)">toPlainObject</a></li>
<li><a href="./toSafeInteger" title="_.toSafeInteger(value)">toSafeInteger</a></li>
<li><a href="./toString" title="_.toString(value)">toString</a></li>
</ul></li>
<li id="page-tree-math" class="folder"><span class="folderPage">Math</span>
<ul>
<li><a href="./add" title="_.add(augend, addend)">add</a></li>
<li><a href="./ceil" title="_.ceil(number, [precision=0])">ceil</a></li>
<li><a href="./floor" title="_.floor(number, [precision=0])">floor</a></li>
<li><a href="./max" title="_.max(array)">max</a></li>
<li><a href="./maxBy" title="_.maxBy(array, [iteratee=_.identity])">maxBy</a></li>
<li><a href="./mean" title="_.mean(array)">mean</a></li>
<li><a href="./min" title="_.min(array)">min</a></li>
<li><a href="./minBy" title="_.minBy(array, [iteratee=_.identity])">minBy</a></li>
<li><a href="./round" title="_.round(number, [precision=0])">round</a></li>
<li><a href="./subtract" title="_.subtract(minuend, subtrahend)">subtract</a></li>
<li><a href="./sum" title="_.sum(array)">sum</a></li>
<li><a href="./sumBy" title="_.sumBy(array, [iteratee=_.identity])">sumBy</a></li>
</ul></li>
<li id="page-tree-methods" class="folder"><span class="folderPage">Methods</span>
<ul>
<li><a href="./templateSettings-imports-_" title="_.templateSettings.imports._">templateSettings.imports._</a></li>
</ul></li>
<li id="page-tree-number" class="folder"><span class="folderPage">Number</span>
<ul>
<li><a href="./clamp" title="_.clamp(number, [min], max)">clamp</a></li>
<li><a href="./inRange" title="_.inRange(number, [start=0], end)">inRange</a></li>
<li><a href="./random" title="_.random([min=0], [max=1], [floating])">random</a></li>
</ul></li>
<li id="page-tree-object" class="folder"><span class="folderPage">Object</span>
<ul>
<li><a href="./assign" title="_.assign(object, [sources])">assign</a></li>
<li><a href="./assignIn" title="_.assignIn(object, [sources])">assignIn <span class="aliases">extend</span></a></li>
<li><a href="./assignInWith" title="_.assignInWith(object, sources, [customizer])">assignInWith <span class="aliases">extendWith</span></a></li>
<li><a href="./assignWith" title="_.assignWith(object, sources, [customizer])">assignWith</a></li>
<li><a href="./at" title="_.at(object, [paths])">at</a></li>
<li><a href="./create" title="_.create(prototype, [properties])">create</a></li>
<li><a href="./defaults" title="_.defaults(object, [sources])">defaults</a></li>
<li><a href="./defaultsDeep" title="_.defaultsDeep(object, [sources])">defaultsDeep</a></li>
<li><a href="./findKey" title="_.findKey(object, [predicate=_.identity])">findKey</a></li>
<li><a href="./findLastKey" title="_.findLastKey(object, [predicate=_.identity])">findLastKey</a></li>
<li><a href="./forIn" title="_.forIn(object, [iteratee=_.identity])">forIn</a></li>
<li><a href="./forInRight" title="_.forInRight(object, [iteratee=_.identity])">forInRight</a></li>
<li><a href="./forOwn" title="_.forOwn(object, [iteratee=_.identity])">forOwn</a></li>
<li><a href="./forOwnRight" title="_.forOwnRight(object, [iteratee=_.identity])">forOwnRight</a></li>
<li><a href="./functions" title="_.functions(object)">functions</a></li>
<li><a href="./functionsIn" title="_.functionsIn(object)">functionsIn</a></li>
<li><a href="./get" title="_.get(object, path, [defaultValue])">get</a></li>
<li><a href="./has" title="_.has(object, path)">has</a></li>
<li><a href="./hasIn" title="_.hasIn(object, path)">hasIn</a></li>
<li><a href="./invert" title="_.invert(object, [multiVal])">invert</a></li>
<li><a href="./invertBy" title="_.invertBy(object, [iteratee=_.identity])">invertBy</a></li>
<li><a href="./invoke" title="_.invoke(object, path, [args])">invoke</a></li>
<li><a href="./keys" title="_.keys(object)">keys</a></li>
<li><a href="./keysIn" title="_.keysIn(object)">keysIn</a></li>
<li><a href="./mapKeys" title="_.mapKeys(object, [iteratee=_.identity])">mapKeys</a></li>
<li><a href="./mapValues" title="_.mapValues(object, [iteratee=_.identity])">mapValues</a></li>
<li><a href="./merge" title="_.merge(object, [sources])">merge</a></li>
<li><a href="./mergeWith" title="_.mergeWith(object, sources, customizer)">mergeWith</a></li>
<li><a href="./omit" title="_.omit(object, [props])">omit</a></li>
<li><a href="./omitBy" title="_.omitBy(object, [predicate=_.identity])">omitBy</a></li>
<li><a href="./pick" title="_.pick(object, [props])">pick</a></li>
<li><a href="./pickBy" title="_.pickBy(object, [predicate=_.identity])">pickBy</a></li>
<li><a href="./result" title="_.result(object, path, [defaultValue])">result</a></li>
<li><a href="./set" title="_.set(object, path, value)">set</a></li>
<li><a href="./setWith" title="_.setWith(object, path, value, [customizer])">setWith</a></li>
<li><a href="./toPairs" title="_.toPairs(object)">toPairs</a></li>
<li><a href="./toPairsIn" title="_.toPairsIn(object)">toPairsIn</a></li>
<li><a href="./transform" title="_.transform(object, [iteratee=_.identity], [accumulator])">transform</a></li>
<li><a href="./unset" title="_.unset(object, path)">unset</a></li>
<li><a href="./values" title="_.values(object)">values</a></li>
<li><a href="./valuesIn" title="_.valuesIn(object)">valuesIn</a></li>
</ul></li>
<li id="page-tree-properties" class="folder"><span class="folderPage">Properties</span>
<ul>
<li><a href="./templateSettings" title="_.templateSettings">templateSettings</a></li>
<li><a href="./templateSettings-escape" title="_.templateSettings.escape">templateSettings.escape</a></li>
<li><a href="./templateSettings-evaluate" title="_.templateSettings.evaluate">templateSettings.evaluate</a></li>
<li><a href="./templateSettings-imports" title="_.templateSettings.imports">templateSettings.imports</a></li>
<li><a href="./templateSettings-interpolate" title="_.templateSettings.interpolate">templateSettings.interpolate</a></li>
<li><a href="./templateSettings-variable" title="_.templateSettings.variable">templateSettings.variable</a></li>
<li><a href="./VERSION" title="_.VERSION">VERSION</a></li>
</ul></li>
<li id="page-tree-seq" class="folder"><span class="folderPage">Seq</span>
<ul>
<li><a href="./_" title="_(value)">_</a></li>
<li><a href="./chain" title="_.chain(value)">chain</a></li>
<li><a href="./prototype-at" title="_.prototype.at([paths])">prototype.at</a></li>
<li><a href="./prototype-chain" title="_.prototype.chain()">prototype.chain</a></li>
<li><a href="./prototype-commit" title="_.prototype.commit()">prototype.commit</a></li>
<li><a href="./prototype-next" title="_.prototype.next()">prototype.next</a></li>
<li><a href="./prototype-plant" title="_.prototype.plant(value)">prototype.plant</a></li>
<li><a href="./prototype-Symbol-iterator" title="_.prototype.Symbol.iterator()">prototype.Symbol.iterator</a></li>
<li><a href="./prototype-value" title="_.prototype.value()">prototype.value <span class="aliases">run, toJSON, valueOf</span></a></li>
<li><a href="./tap" title="_.tap(value, interceptor)">tap</a></li>
<li><a href="./thru" title="_.thru(value, interceptor)">thru</a></li>
<li><a href="./wrapperFlatMap" title="_.wrapperFlatMap([iteratee=_.identity])">wrapperFlatMap</a></li>
</ul></li>
<li id="page-tree-string" class="folder"><span class="folderPage">String</span>
<ul>
<li><a href="./camelCase" title="_.camelCase([string=&#39;&#39;])">camelCase</a></li>
<li><a href="./capitalize" title="_.capitalize([string=&#39;&#39;])">capitalize</a></li>
<li><a href="./deburr" title="_.deburr([string=&#39;&#39;])">deburr</a></li>
<li><a href="./endsWith" title="_.endsWith([string=&#39;&#39;], [target], [position=string.length])">endsWith</a></li>
<li><a href="./escape" title="_.escape([string=&#39;&#39;])">escape</a></li>
<li><a href="./escapeRegExp" title="_.escapeRegExp([string=&#39;&#39;])">escapeRegExp</a></li>
<li><a href="./kebabCase" title="_.kebabCase([string=&#39;&#39;])">kebabCase</a></li>
<li><a href="./lowerCase" title="_.lowerCase([string=&#39;&#39;])">lowerCase</a></li>
<li><a href="./lowerFirst" title="_.lowerFirst([string=&#39;&#39;])">lowerFirst</a></li>
<li><a href="./pad" title="_.pad([string=&#39;&#39;], [length=0], [chars=&#39; &#39;])">pad</a></li>
<li><a href="./padEnd" title="_.padEnd([string=&#39;&#39;], [length=0], [chars=&#39; &#39;])">padEnd</a></li>
<li><a href="./padStart" title="_.padStart([string=&#39;&#39;], [length=0], [chars=&#39; &#39;])">padStart</a></li>
<li><a href="./parseInt" title="_.parseInt(string, [radix])">parseInt</a></li>
<li><a href="./repeat" title="_.repeat([string=&#39;&#39;], [n=0])">repeat</a></li>
<li><a href="./replace" title="_.replace([string=&#39;&#39;], pattern)">replace</a></li>
<li><a href="./snakeCase" title="_.snakeCase([string=&#39;&#39;])">snakeCase</a></li>
<li><a href="./split" title="_.split([string=&#39;&#39;], [separator], [limit])">split</a></li>
<li><a href="./startCase" title="_.startCase([string=&#39;&#39;])">startCase</a></li>
<li><a href="./startsWith" title="_.startsWith([string=&#39;&#39;], [target], [position=0])">startsWith</a></li>
<li><a href="./template" title="_.template([string=&#39;&#39;], [options])">template</a></li>
<li><a href="./toLower" title="_.toLower([string=&#39;&#39;])">toLower</a></li>
<li><a href="./toUpper" title="_.toUpper([string=&#39;&#39;])">toUpper</a></li>
<li><a href="./trim" title="_.trim([string=&#39;&#39;], [chars=whitespace])">trim</a></li>
<li><a href="./trimEnd" title="_.trimEnd([string=&#39;&#39;], [chars=whitespace])">trimEnd</a></li>
<li><a href="./trimStart" title="_.trimStart([string=&#39;&#39;], [chars=whitespace])">trimStart</a></li>
<li><a href="./truncate" title="_.truncate([string=&#39;&#39;], [options])">truncate</a></li>
<li><a href="./unescape" title="_.unescape([string=&#39;&#39;])">unescape</a></li>
<li><a href="./upperCase" title="_.upperCase([string=&#39;&#39;])">upperCase</a></li>
<li><a href="./upperFirst" title="_.upperFirst([string=&#39;&#39;])">upperFirst</a></li>
<li><a href="./words" title="_.words([string=&#39;&#39;], [pattern])">words</a></li>
</ul></li>
<li id="page-tree-util" class="folder"><span class="folderPage">Util</span>
<ul>
<li><a href="./attempt" title="_.attempt(func)">attempt</a></li>
<li><a href="./bindAll" title="_.bindAll(object, methodNames)">bindAll</a></li>
<li><a href="./cond" title="_.cond(pairs)">cond</a></li>
<li><a href="./conforms" title="_.conforms(source)">conforms</a></li>
<li><a href="./constant" title="_.constant(value)">constant</a></li>
<li><a href="./flow" title="_.flow([funcs])">flow</a></li>
<li><a href="./flowRight" title="_.flowRight([funcs])">flowRight</a></li>
<li><a href="./identity" title="_.identity(value)">identity</a></li>
<li><a href="./iteratee" title="_.iteratee([func=_.identity])">iteratee</a></li>
<li><a href="./matches" title="_.matches(source)">matches</a></li>
<li><a href="./matchesProperty" title="_.matchesProperty(path, srcValue)">matchesProperty</a></li>
<li><a href="./method" title="_.method(path, [args])">method</a></li>
<li><a href="./methodOf" title="_.methodOf(object, [args])">methodOf</a></li>
<li><a href="./mixin" title="_.mixin([object=lodash], source, [options])">mixin</a></li>
<li><a href="./noConflict" title="_.noConflict()">noConflict</a></li>
<li><a href="./noop" title="_.noop()">noop</a></li>
<li><a href="./nthArg" title="_.nthArg([n=0])">nthArg</a></li>
<li><a href="./over" title="_.over(iteratees)">over</a></li>
<li><a href="./overEvery" title="_.overEvery(predicates)">overEvery</a></li>
<li><a href="./overSome" title="_.overSome(predicates)">overSome</a></li>
<li><a href="./property" title="_.property(path)">property</a></li>
<li><a href="./propertyOf" title="_.propertyOf(object)">propertyOf</a></li>
<li><a href="./range" title="_.range([start=0], end, [step=1])">range</a></li>
<li><a href="./rangeRight" title="_.rangeRight([start=0], end, [step=1])">rangeRight</a></li>
<li><a href="./runInContext" title="_.runInContext([context=root])">runInContext</a></li>
<li><a href="./times" title="_.times(n, [iteratee=_.identity])">times</a></li>
<li><a href="./toPath" title="_.toPath(value)">toPath</a></li>
<li><a href="./uniqueId" title="_.uniqueId([prefix])">uniqueId</a></li>
</ul></li>
</ul>
    </div>

</nav>

<div id="main" onclick="">
    <div id="content" class="markdown-body">
        <div data-render-page="entry"><h2>groupBy <a class="fa-link" href="./groupBy" title="Link to this entry.">&#xf0c1;</a> <a href="https://github.com/lodash/lodash/blob/4.5.0正式版/lodash.src.js#L7749" title="View in source." target="github">source</a> <a href="https://www.npmjs.com/package/lodash.groupby" title="See the npm package." target="npm">npm</a></h2>
<div class="signature">_.groupBy(collection, [iteratee&#x3D;_.identity])</div>

<div data-render-html="/groupBy"><p>创建一个对象组成，key 是经 iteratee 处理的结果， value 是产生 key 的元素数组。 iteratee 会传入1个参数：(value)。</p>
</div>

<h3>参数</h3>
    <ol>
<li><span class="param-name">collection</span> <span class="param-type">(Array|Object)</span> <div data-render-html="/#synthetic"><p>需要遍历的集合 </p>
</div></li>
<li><span class="param-name">[iteratee&#x3D;_.identity]</span> <span class="param-type">(Function|Object|string)</span> <div data-render-html="/#synthetic"><p>这个函数会处理每一个元素 </p>
</div></li>
    </ol>
<h3>返回值 <span class="return-type">(Object)</span></h3>
    <div class="returns"> <div data-render-html="/#synthetic"><p> 返回一个组成汇总的对象</p>
</div></div>
<h3>示例</h3>
    <div data-render-html="/#synthetic"><pre><code class="lang-js">_<span class="token punctuation" >.</span><span class="token function" >groupBy</span><span class="token punctuation" >(</span><span class="token punctuation" >[</span><span class="token number" >6.1</span><span class="token punctuation" >,</span> <span class="token number" >4.2</span><span class="token punctuation" >,</span> <span class="token number" >6.3</span><span class="token punctuation" >]</span><span class="token punctuation" >,</span> Math<span class="token punctuation" >.</span>floor<span class="token punctuation" >)</span><span class="token punctuation" >;</span>
<span class="token comment" spellcheck="true">// => { '4': [4.2], '6': [6.1, 6.3] }</span>

<span class="token comment" spellcheck="true">// 使用了 `_.property` 的回调结果</span>
_<span class="token punctuation" >.</span><span class="token function" >groupBy</span><span class="token punctuation" >(</span><span class="token punctuation" >[</span><span class="token string" >'one'</span><span class="token punctuation" >,</span> <span class="token string" >'two'</span><span class="token punctuation" >,</span> <span class="token string" >'three'</span><span class="token punctuation" >]</span><span class="token punctuation" >,</span> <span class="token string" >'length'</span><span class="token punctuation" >)</span><span class="token punctuation" >;</span>
<span class="token comment" spellcheck="true">// => { '3': ['one', 'two'], '5': ['three'] }</span>
</code></pre>
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