我正在尝试在大数据框（每分钟数据）中提取值，当x变量处于每日最小值和最大值时，我想要数据帧的子集。
有关示例数据集，请参见下文。我给出的示例具有每日值以降低复杂性 - 因此在这种情况下，当温度达到最小值和最大值时，如何获取每月数据帧值。
我没有大量的经验，但我已经能够提取每月最小和最大温度值：
a <- as.data.frame(aggregate(df$Temp, df[4], function(x) {
c(max = max(x), min = min(x)) }))
但我不确定如何在不丢失原始数据框的信息的情况下做到这一点 - 它几乎是基于最小和最大参数的子集？但我不知道该怎么写。
任何帮助都将受到赞赏 - 并为大型dput示例道歉。 感谢
df <- structure(list(Group.1 = c(1628, 1629, 1630, 1631, 1632, 1633,
1634, 1635, 1636, 1637, 1638, 1639, 1640, 1641, 1642, 1643, 1644,
1645, 1646, 1647, 1648, 1649, 1650, 1651, 1652, 1653, 1654, 1655,
1656, 1657, 1658, 1659, 1660, 1661, 1662, 1663, 1664, 1665, 1666,
1667, 1668, 1669, 1670, 1671, 1672, 1673, 1674, 1675, 1676),
datetime = structure(c(1466078376.13352, 1466164800, 1466251194.49235,
1466337600, 1466423992.99026, 1466510400, 1466596853.49096,
1466683185.13551, 1466769600, 1466856000.06254, 1466942345.50765,
1467028800, 1467115179.92356, 1467201600, 1467288000, 1467374400,
1467460801.81376, 1467547200, 1467633604.67316, 1467720000,
1467806423.20361, 1467892800, 1467979255.99444, 1468065552.68428,
1468152000, 1468238400, 1468324827.121, 1468411200, 1468497619.36762,
1468584000, 1468670456.74548, 1468756798.41446, 1468843200,
1468928779.09091, 1469016500.50633, 1469102400, 1469188805.17385,
1469275200, 1469361564.70097, 1469448000, 1469534423.82046,
1469620800, 1469707247.98331, 1469793556.6064, 1469880000,
1469966391.40473, 1470041370, 1470178341.25, 1470217984.93671
), class = c("POSIXct", "POSIXt")), year = c(2016, 2016,
2016, 2016, 2016, 2016, 2016, 2016, 2016, 2016, 2016, 2016,
2016, 2016, 2016, 2016, 2016, 2016, 2016, 2016, 2016, 2016,
2016, 2016, 2016, 2016, 2016, 2016, 2016, 2016, 2016, 2016,
2016, 2016, 2016, 2016, 2016, 2016, 2016, 2016, 2016, 2016,
2016, 2016, 2016, 2016, 2016, 2016, 2016), month = c(6, 6,
6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7,
7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
7, 7, 7, 7, 7, 7, 8, 8, 8), day = c(16, 17, 18, 19, 20, 21,
22, 23, 24, 25, 26, 27, 28, 29, 30, 1, 2, 3, 4, 5, 6, 7,
8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22,
23, 24, 25, 26, 27, 28, 29, 30, 31, 1, 2, 3), hour = c(11.4937413073713,
11.5, 11.4979137691238, 11.5, 11.4979137691238, 11.5, 11.5146036161335,
11.4961779013204, 11.5, 11.5003474635163, 11.4853963838665,
11.5, 11.4940931202224, 11.5, 11.5, 11.5, 11.5003474635163,
11.5, 11.5006954102921, 11.5, 11.5066018068103, 11.5, 11.5159944367177,
11.4867872044506, 11.5, 11.5, 11.5076495132128, 11.5, 11.505211952745,
11.5, 11.5159944367177, 11.4993045897079, 11.5, 11.2755681818182,
11.6385372714487, 11.5, 11.5020862308762, 11.5, 11.4895688456189,
11.5, 11.5066109951287, 11.5, 11.5132127955494, 11.4881780250348,
11.5, 11.4979137691238, 8.3314447592068, 22.3854166666667,
9.38818565400844), min = c(29.4777468706537, 29.5, 29.5333796940195,
29.5, 29.5083449235049, 29.5, 29.5152990264256, 29.4815844336345,
29.5, 29.4801945795691, 29.4680111265647, 29.5, 29.5198054204309,
29.5, 29.5, 29.5, 29.5093815149409, 29.5, 29.5361613351878,
29.5, 29.4906184850591, 29.5, 29.4735744089013, 29.5041724617524,
29.5, 29.5, 29.4930458970793, 29.5, 29.5100764419736, 29.5,
29.4860917941586, 29.5152990264256, 29.5, 29.2840909090909,
29.5295358649789, 29.5, 29.4610570236439, 29.5, 29.5375521557719,
29.5, 29.500347947112, 29.5, 29.5069541029207, 29.4860917941586,
29.5, 29.4819193324061, 29.1133144475921, 28.7291666666667,
29.2911392405063), sec = c(30, 30, 30, 30, 30, 30, 30, 30,
30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30,
30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30,
30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30), DOY = c(167.499723767578,
168.5, 169.499936254057, 170.5, 171.499918868799, 172.5,
173.500619108329, 174.499827957301, 175.5, 176.500000723882,
177.499369301499, 178.5, 179.499767633773, 180.5, 181.5,
182.5, 183.500020992587, 184.5, 185.500054087467, 186.5,
187.500268560343, 188.5, 189.500648083758, 190.499452364395,
191.5, 192.5, 193.500313900479, 194.5, 195.500224162227,
196.5, 197.500656776387, 198.499981648895, 199.5, 200.490498737374,
201.505792897328, 202.5, 203.500059882553, 204.5, 205.499591446453,
206.5, 207.50027569976, 208.5, 209.500555362386, 210.499497759233,
211.5, 212.499900517694, 213.367708333333, 214.953023726852,
215.41186269339), Day = c(1628.49972376758, 1629.5, 1630.49993625406,
1631.5, 1632.4999188688, 1633.5, 1634.50061910833, 1635.4998279573,
1636.5, 1637.50000072388, 1638.4993693015, 1639.5, 1640.49976763377,
1641.5, 1642.5, 1643.5, 1644.50002099259, 1645.5, 1646.50005408747,
1647.5, 1648.50026856034, 1649.5, 1650.50064808376, 1651.49945236439,
1652.5, 1653.5, 1654.50031390048, 1655.5, 1656.50022416223,
1657.5, 1658.50065677639, 1659.4999816489, 1660.5, 1661.49049873737,
1662.50579289733, 1663.5, 1664.50005988255, 1665.5, 1666.49959144645,
1667.5, 1668.50027569976, 1669.5, 1670.50055536239, 1671.49949775923,
1672.5, 1673.49990051769, 1674.36770833333, 1675.95302372685,
1676.41186269339), DayH = c(1628.47890588781, 1629.47916666667,
1630.47907974038, 1631.47916666667, 1632.47907974038, 1633.47916666667,
1634.47977515067, 1635.47900741256, 1636.47916666667, 1637.47918114431,
1638.47855818266, 1639.47916666667, 1640.47892054668, 1641.47916666667,
1642.47916666667, 1643.47916666667, 1644.47918114431, 1645.47916666667,
1646.4791956421, 1647.47916666667, 1648.47944174195, 1649.47916666667,
1650.47983310153, 1651.47861613352, 1652.47916666667, 1653.47916666667,
1654.47948539638, 1655.47916666667, 1656.47938383136, 1657.47916666667,
1658.47983310153, 1659.47913769124, 1660.47916666667, 1661.46981534091,
1662.48493905298, 1663.47916666667, 1664.47925359295, 1665.47916666667,
1666.47873203523, 1667.47916666667, 1668.4794421248, 1669.47916666667,
1670.47971719981, 1671.47867408438, 1672.47916666667, 1673.47907974038,
1674.34714353163, 1675.93272569444, 1676.39117440225), DayD = c(1628,
1629, 1630, 1631, 1632, 1633, 1634, 1635, 1636, 1637, 1638,
1639, 1640, 1641, 1642, 1643, 1644, 1645, 1646, 1647, 1648,
1649, 1650, 1651, 1652, 1653, 1654, 1655, 1656, 1657, 1658,
1659, 1660, 1661, 1662, 1663, 1664, 1665, 1666, 1667, 1668,
1669, 1670, 1671, 1672, 1673, 1674, 1675, 1676), Sal = c(29.0488087045063,
29.0242089236389, 28.9704142552782, 28.9337236612778, 28.9124731267455,
28.8621913531181, 28.7694603506606, 28.6800432876789, 28.6368648858889,
28.5239238692008, 28.6274684358136, 28.6899766423333, 28.7094982390063,
28.6427974009653, 28.6540963996528, 28.5762126331528, 28.5617631359555,
28.6364940399097, 28.6458543031711, 28.603713066875, 28.65796586713,
28.6926140346389, 28.6470827340195, 28.5985220503964, 28.6620416165972,
28.6305870582222, 28.7001961730876, 28.6916165265, 28.6656868092356,
28.8356597378472, 29.266969874235, 28.418354432114, 28.3670879136597,
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28.1165695540903, 28.6652365165229, 28.4222878245758, 28.4388172580139,
28.0149544998192, 28.4748151350047, 28.0933474488542, 27.8804163691308
), Temp = c(-0.902727819368567, -0.824054421545139, -0.720653055488178,
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1.24940833146181, 0.780415736372869, 2.0088144469993, 2.93373915290972,
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1.68971783634167, 2.8011089384096, 1.70051260145987, 2.9201268373125,
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), Press = c(1010.94713220445, 1000.91298554167, 987.981428212796,
1003.31839191667, 1010.80608631433, 1010.70622420833, 1014.20480271905,
1018.25909922168, 1017.2977571875, 1017.2116500139, 1014.43729111961,
1016.86667607639, 1017.77638776233, 1017.73254004861, 1017.58831039583,
1023.96083316667, 1023.37822454482, 1018.61740789583, 1017.69460385953,
1019.06393609722, 1019.70283468381, 1021.57185751389, 1022.54906664812,
1019.93420589013, 1015.60680218056, 1013.92687847222, 1018.10282961752,
1017.75759179861, 1011.06972191105, 1000.6753998125, 1006.33157139777,
1010.47605901252, 1004.2360214375, 1003.47128640625, 1005.9544021519,
1002.94591790972, 998.129144311544, 994.845405819444, 996.572536383866,
1007.62132047917, 1015.58149314544, 1015.31391086806, 1014.80282973574,
1014.86646130737, 1011.12184847917, 1007.64412461752, 1008.94791512748,
1016.38731552083, 1014.23599833755), Ts = c(0.0939091805522304,
0.0933571324389885, 0.0926315816934272, 0.0920807064972713,
0.0914849244286843, 0.0906487390808381, 0.0903508008513881,
0.0896503398391888, 0.0894158788365697, 0.0886992027701387,
0.089002314704399, 0.0889635640417059, 0.0885111330762104,
0.0879720536464657, 0.0877271381692247, 0.0866953766257083,
0.0859020961040837, 0.0856618525704464, 0.0853887527876392,
0.0848241204226848, 0.0847934498305695, 0.0842374892345861,
0.0833158824031102, 0.0830544806008765, 0.0829096777186984,
0.0824718703347108, 0.0826933403725865, 0.0822988121621235,
0.0817369399215142, 0.0842685237873781, 0.0888896196011912,
0.079656634577284, 0.0788127760214962, 0.0821017792323535,
0.0734881871639127, 0.0670067820465301, 0.065144627947714,
0.0653888659545473, 0.0744405166847922, 0.0753679790243025,
0.0700098285152706, 0.0717215346483428, 0.0791058326941815,
0.0760274126969679, 0.0757251777215326, 0.0679345115120072,
0.0756495928144236, 0.0670994071000443, 0.0638174503450037
), C = c(8.94065543989075, 8.91870846791228, 8.89129215782166,
8.87041424509199, 8.84686764433126, 8.81516998854457, 8.8084814071784,
8.78498979939825, 8.77801254243485, 8.75556135353215, 8.76169863848835,
8.75623839427317, 8.73659381953759, 8.71875839369915, 8.7081454153551,
8.67125827547341, 8.64042586696951, 8.62643884773293, 8.61505698749588,
8.59531077426103, 8.59085475620887, 8.56693513415321, 8.53362826949292,
8.5263455666875, 8.51701535738585, 8.50192437544613, 8.50643587795999,
8.49224025025525, 8.47229959883608, 8.56396191736222, 8.71907216880554,
8.40708575426135, 8.37898781319225, 8.48450883536676, 8.19834292777621,
8.02742642860397, 7.94335742141408, 7.96038019864108, 8.22636890956846,
8.25191633282365, 8.08596024446269, 8.14084822127661, 8.37247267374788,
8.27175018847621, 8.25980001007453, 8.01532360653014, 8.25581090260999,
7.97597778883369, 7.87850954070042), deltaO = c(-0.539176713575035,
-0.529336754450473, -0.476151386602607, -0.448891301785048,
-0.371478851019715, -0.316365244164706, -0.333759503164495,
-0.20842997042327, -0.158570194489716, -0.139788057771207,
-0.0695596740252039, -0.0670222956453951, -0.0451740767961,
-0.00881028606789499, -0.0196267560794031, 0.00270837075506498,
0.12885503580047, 0.1753403507129, 0.190233674930407, 0.166455606850779,
0.11386372656667, 0.164625003223876, 0.23281525042711, 0.235457512873693,
0.280531394116234, 0.289459150996232, 0.244089148550445,
0.22045630813919, 0.214383555302208, 0.0402743546113934,
-0.0932279238208418, 0.136724628502207, 0.286027328827889,
0.219593839499005, 0.207415604135885, 0.0222562826932507,
-0.0187427504578891, -0.0469711613535759, 0.18669337036061,
0.281291046513154, 0.25224424068066, 0.243330127375477, 0.251581334616514,
0.153326651891512, NaN, 0.285793738567012, 0.229954063047229,
0.30984651152048, 0.0904119306717343), k = c(1.3843960648632,
6.67024147531018, 21.4898676969447, 12.6511158639218, 2.86455163396347,
1.18964832218751, 2.48536575543307, 6.11457188358869, 2.22117060425211,
1.39709711243724, 3.15681260593466, 1.69087035092879, 1.96031515063071,
3.05646023068449, 3.88091903012736, 5.89522588325253, 4.61191456284459,
9.9876497231258, 5.87859816406069, 5.25567516554151, 2.66410131584561,
1.91750845984603, 0.912508517423828, 0.788437993630362, 1.51297375451523,
4.1010391646833, 6.69386108760172, 6.60202002300452, 15.3120378300758,
17.0865393002387, 10.0683520284002, 7.04605349774694, 7.06555793241213,
11.2155892631143, 6.95932652757971, 10.5460039186381, 14.4457642190408,
11.1713965641408, 5.13491665227681, 9.17952853060783, 7.55395359942885,
9.93963153178716, 10.7556273136677, 2.74976182917367, 4.24852415082047,
7.44862825836769, 2.51232305022297, 3.16831051334729, 1.58255842462718
), NCP = c(-6555.51823916664, -30259.5423200574, -93284.1485540249,
-52785.5627897263, -9203.47328702618, -3474.14113092716,
-6643.58632076862, -11084.7222504768, -2779.86321684949,
-1481.582285219, -1974.24446012626, -1018.46398725869, -689.919166266737,
1680.8563208385, -442.391803921574, -180.816469873293, 5330.66701930139,
16192.8444708129, 10544.1353158852, 8370.10647897766, 2991.63246971473,
2741.5747232174, 1716.98452107368, 1723.27625157814, 3806.41762190115,
10674.6146528716, 15783.1240720338, 14337.3594334794, 30669.7204136871,
3257.08033198347, -8574.53718630027, 10409.6993939132, 17974.5471722579,
22284.8034527993, 11849.079774671, 7706.03700970845, 2652.66574996729,
-10421.7431381603, 8448.71926418016, 24212.1390873852, 18754.1407791307,
21358.338661014, 22616.1137584938, 3695.2416322836, NaN,
18437.8290676373, 4903.94862723591, 8770.18358118303, 1206.37283774814
)), .Names = c("Group.1", "datetime", "year", "month", "day",
"hour", "min", "sec", "DOY", "Day", "DayH", "DayD", "Sal", "Temp",
"Den", "Chl", "O2", "ID", "PAR", "CO2", "IR", "Wind", "AirTemp",
"Press", "Ts", "C", "deltaO", "k", "NCP"), row.names = 1324:1372, class
= "data.frame")
答案 0 :(得分：2)
如果您要查找的输出是具有相同df值的所有行中具有最大或最小Temp的{{1}}行的子集，则：
month