R ploting one of two boxplots in ggplot

Question

I have a data frame with a column representing each step of simulations and I want to plot every two steps of simulation ...

Example :

a=structure(list(X.step. = c(0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 1L, 
1L, 1L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 3L, 
3L, 3L, 3L, 3L, 3L, 3L, 4L, 3L, 4L, 4L, 4L, 4L, 4L, 5L, 4L, 5L, 
5L, 4L, 5L, 5L, 6L, 5L, 5L, 6L, 6L, 6L, 7L, 6L, 5L, 6L, 6L, 7L, 
7L, 7L, 8L, 7L, 6L, 7L, 7L, 8L, 8L, 9L, 8L, 8L, 7L, 8L, 9L, 8L, 
9L, 9L, 9L, 8L, 9L, 9L, 9L, 0L, 1L, 0L, 2L, 0L, 3L, 1L, 0L, 4L, 
1L, 2L, 1L, 5L, 2L, 3L, 2L, 6L, 3L, 4L, 3L, 7L, 4L, 8L, 5L, 4L, 
9L, 5L, 0L, 6L, 5L, 6L, 6L, 7L, 1L, 7L, 7L, 8L, 2L, 8L, 8L, 9L, 
3L, 9L, 9L, 0L, 4L, 1L, 5L, 2L, 6L, 3L, 7L, 4L, 8L, 9L, 5L, 0L, 
6L, 1L, 7L, 2L, 8L, 3L, 9L, 4L, 5L, 0L, 6L, 1L, 7L, 2L, 8L, 3L, 
9L, 4L, 5L, 6L, 7L, 8L, 9L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 
9L, 0L, 1L, 0L, 2L, 1L, 3L, 4L, 2L, 5L, 0L, 3L, 6L, 4L, 1L, 7L, 
5L, 2L, 8L, 6L, 3L, 9L, 7L, 4L, 8L, 5L, 9L, 6L, 7L, 8L, 9L, 0L, 
1L, 2L, 3L, 4L, 5L, 6L, 7L, 0L, 8L, 9L, 1L, 2L, 3L, 4L, 0L, 5L, 
1L, 6L, 2L, 7L, 3L, 8L, 4L, 9L, 5L, 6L, 7L, 8L, 0L, 9L, 1L, 2L, 
3L, 4L, 5L, 6L, 7L, 8L, 9L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 
9L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L, 0L, 1L, 2L, 3L, 4L, 
5L, 0L, 6L, 1L, 7L, 8L, 2L, 9L, 3L, 4L, 5L, 6L, 7L, 8L, 9L, 0L, 
1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L, 0L, 1L, 0L, 2L, 1L, 3L, 2L, 
4L, 3L, 5L, 4L, 6L, 5L, 7L, 6L, 8L, 7L, 9L, 8L, 9L, 0L, 1L, 0L, 
2L, 1L, 3L, 4L, 2L, 5L, 3L, 6L, 4L, 7L, 8L, 5L, 9L, 6L, 7L, 8L, 
9L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L, 0L, 1L, 2L, 3L, 4L, 
5L, 6L, 7L, 8L, 9L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L, 0L, 
1L, 2L, 3L, 4L, 5L, 0L, 6L, 1L, 2L, 7L, 3L, 8L, 4L, 9L, 5L, 6L, 
7L, 8L, 9L, 0L, 0L, 1L, 2L, 1L, 3L, 2L, 4L, 3L, 5L, 4L, 6L, 5L, 
7L, 6L, 8L, 7L, 9L, 8L, 9L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 
9L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 0L, 9L, 1L, 2L, 3L, 4L, 
5L, 6L, 7L, 8L, 9L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 0L, 9L, 
1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 
7L, 8L, 9L, 0L, 1L, 2L, 3L, 4L, 5L, 0L, 6L, 1L, 7L, 8L, 2L, 9L, 
3L, 4L, 5L, 6L, 7L, 8L, 9L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 0L, 
8L, 1L, 9L, 2L, 3L, 4L, 5L, 6L, 7L, 0L, 8L, 9L, 1L, 2L, 3L, 4L, 
5L, 6L, 0L, 7L, 1L, 8L, 2L, 9L, 3L, 4L, 5L, 6L, 7L, 8L, 9L, 0L, 
1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L, 0L, 1L, 2L, 0L, 3L, 1L, 4L, 
5L, 2L, 6L, 3L, 7L, 4L, 8L, 5L, 9L, 6L, 7L, 8L, 9L, 0L, 1L, 2L, 
3L, 4L, 5L, 0L, 6L, 1L, 7L, 2L, 8L, 3L, 9L, 4L, 5L, 6L, 7L, 8L, 
9L, 0L, 1L, 2L, 3L, 0L, 4L, 1L, 5L, 6L, 2L, 7L, 3L, 8L, 9L, 4L, 
5L, 6L, 7L, 0L, 8L, 1L, 9L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L, 0L, 
1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L, 0L, 1L, 2L, 3L, 4L, 0L, 5L, 
1L, 0L, 6L, 1L, 2L, 7L, 2L, 8L, 3L, 3L, 9L, 4L, 4L, 5L, 5L, 6L, 
6L, 7L, 0L, 7L, 8L, 9L, 1L, 8L, 9L, 2L, 0L, 3L, 1L, 4L, 2L, 5L, 
3L, 6L, 4L, 7L, 5L, 8L, 6L, 7L, 9L, 8L, 9L, 0L, 1L, 2L, 3L, 4L, 
5L, 6L, 7L, 8L, 9L, 0L, 1L, 2L, 0L, 3L, 1L, 4L, 2L, 5L, 3L, 6L, 
4L, 7L, 5L, 8L, 6L, 9L, 7L, 8L, 9L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 
7L, 8L, 9L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L, 0L, 1L, 0L, 
2L, 1L, 3L, 2L, 4L, 3L, 5L, 4L, 6L, 5L, 7L, 6L, 8L, 7L, 0L, 8L, 
9L, 9L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L, 0L, 1L, 2L, 3L, 4L, 
5L, 6L, 7L, 8L, 9L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L, 0L, 
1L, 0L, 2L, 1L, 3L, 2L, 3L, 4L, 4L, 5L, 5L, 6L, 6L, 7L, 7L, 8L, 
8L, 9L, 9L, 0L, 1L, 2L, 3L, 0L, 4L, 1L, 5L, 2L, 6L, 3L, 7L, 4L, 
8L, 5L, 9L, 6L, 7L, 8L, 9L), Capital_Hill = c(5000, 5000, 5000, 
5000, 5000, 5000, 5000, 5000, 20489.7098255422, 18647.9871601902, 
19322.3348318008, 19093.4975515191, 19964.7906013619, 18138.334932914, 
18798.2155161531, 19520.6592243171, 16189.1005720184, 7217.42311821296, 
10385.8517392027, 11587.4833706148, 8745.17771118928, 6364.6857034054, 
8960.36024556284, 10453.9730516154, 11279.5311553941, -1555.43893635276, 
5027.83508494888, -2683.23117756096, 1393.62412797987, 3950.66476922022, 
1177.9334196972, 9668.230146051, 4143.50230043012, -3428.49115061733, 
3872.28690850704, -4812.94494623542, -98.9684645837859, 1883.84198073663, 
11374.5541242187, 714.876295181919, 6221.52489447769, -151.630448506746, 
2888.96694320404, -1781.5636351967, 2106.10431875055, 15491.7176947478, 
4193.02022649885, 4024.29810085155, 5716.76355923053, 11450.8687665758, 
3655.45444702831, 20512.0032927283, 8105.64482179299, 5888.5563712437, 
8418.93101598735, 10166.9785794628, 13118.3548047528, 16715.3090616135, 
10388.5632777236, 26763.0262802347, 14014.2143953517, 10988.773662856, 
15568.4992097975, 17501.7723139078, 22016.7485548592, 23991.3958923051, 
35046.9986075527, 19215.4208912491, 23077.385542937, 18349.4581718549, 
22656.536484305, 29860.9195839098, 23441.0509825286, 32443.7854869624, 
27667.6776201081, 30759.139301094, 25395.7864401077, 31391.1613441541, 
31121.6329421095, 29918.393785456, 5000, 19516.6065775793, 5000, 
9419.32063654092, 5000, 2009.90741864572, 19555.8133004356, 5000, 
-654.02965741475, 19122.9111101632, 11184.8631976067, 17996.6740524179, 
1138.00811312575, 8495.38945039064, 5377.40673624512, 5798.37755337888, 
6508.39137319272, 2309.80804949953, 5453.31413281241, -2711.7378571935, 
13274.8481753427, 2512.54353681405, 20111.5278064519, 9502.77143878391, 
-5462.67280197028, 32565.500094441, 6393.00096339746, 5000, 14973.9608679735, 
-2543.16695364618, 12103.9409020041, 3311.37833549452, 20528.760260385, 
20773.7003425286, 16624.2861222331, 11126.45838254, 28608.1066784694, 
14995.9092263089, 20665.8793669486, 22356.2002525479, 34927.6906707312, 
9537.01445855963, 27949.3379086433, 29962.2664783985, 5000, 8500.45122044844, 
18461.6163874056, 11218.6215583133, 5755.75472677829, 17253.3643660214, 
-4184.18748661031, 24264.2528463904, -7303.94320803012, 31156.3108977128, 
36435.9814961802, -4524.19749453666, 5000, 1688.70739941494, 
20904.9967718526, 9521.71949378518, 17904.6695008067, 17902.2228871932, 
13609.3652797451, 28357.7085338908, 12707.1132235877, 14360.4841173028, 
5000, 18852.9443087615, 20509.6196388613, 24473.7959188055, 13665.3321023317, 
30446.0474400949, 8407.52096769587, 39122.0642115205, 9017.3276434745, 
12697.1620138356, 17646.7303301337, 22996.5955520881, 29146.5762917183, 
35634.6876170914, 5000, 20256.6563305109, 14002.5606956847, 7706.78971502452, 
7650.85410493198, 10585.5481304756, 15247.9120169065, 21228.0529500457, 
28067.5273136216, 33595.2410151807, 5000, 19771.90576498, 5000, 
11519.7862728797, 19287.2014227327, 5230.73409320381, 4098.65791804344, 
8860.11961674494, 6453.46467477849, 5000, 2815.88731781052, 11830.9940041421, 
1481.79046273321, 19719.5523891005, 17195.9681093997, 3493.6477870963, 
11904.4731232913, 24698.6417588021, 8303.69297814839, 4349.86800587358, 
33836.3219241388, 14450.3503670852, 2434.4539017217, 20670.5918746441, 
4588.70618802343, 28728.2181039865, 10165.9327278812, 17056.4749319925, 
23103.1740791684, 30191.0308235334, 5000, 17404.1622061253, 7844.82742537156, 
74.6251748716197, -2727.76784769199, -640.530575222837, 4693.89842856531, 
12065.0155109766, 5000, 21127.7345450589, 28075.0507306847, 16962.739743341, 
5674.35728893149, -4727.61808719137, -8457.81381625247, 5000, 
-6841.64259882885, 17308.5480856169, -460.354477345629, 6594.6017504895, 
7926.86615194192, -1536.84025803668, 17401.9649868518, -2911.75912386691, 
27335.0312567315, -483.614553655837, 4681.33507929712, 12338.2897168989, 
21893.3887182219, 5000, 28450.265783698, 17426.9268383773, 6132.91810130035, 
-1657.60327379152, -3145.89208808826, -677.764904032483, 5168.9071774366, 
12338.1054792169, 18357.5031623822, 26702.189691676, 5000, 17272.5985042244, 
6529.36007349031, -1483.18038982317, -3194.02246725017, -864.539225372793, 
4880.81380433676, 11503.0801744938, 18890.6443464088, 27380.1038151267, 
5000, 16566.4259172581, 4192.05365987776, -4147.32026509126, 
-6180.26521985924, -4328.90716305576, 2617.72939525306, 9810.50240434987, 
16146.8068923361, 24952.044957239, 5000, 16936.1791126631, 4620.54259091373, 
-5395.19541828241, -9160.14511554726, -7094.66028253679, 5000, 
-389.373479395586, 16709.9158206452, 9605.89586577239, 17698.1503683425, 
3392.49550994562, 29003.4431848308, -4975.25418720535, -7081.848544121, 
-5155.30766151213, 833.35566062533, 7825.317981083, 15649.5875640682, 
27510.5345766661, 5000, 17674.2304090849, 8362.60586718016, 1244.14138873582, 
-412.877365183411, 1593.70298089344, 6504.06893348446, 14139.3208140798, 
21158.4294479189, 31069.6504185086, 5000, 18118.8004619832, 5000, 
10335.4457087842, 17084.9827023801, 3611.71013801494, 6929.9946716569, 
2184.41908049661, -1536.15484963268, 4191.81308757483, -5155.56455029937, 
9267.92273531495, -3909.23691911105, 16068.8024043549, 1343.70607136169, 
21939.0298347732, 7629.67857173291, 30850.4636324382, 16888.1276401152, 
26850.8528990615, 5000, 18422.8617842306, 5000, 11607.1131114823, 
16628.9405255433, 5676.03414113105, 4814.00843290827, 3421.2056777451, 
6991.1111390283, -6190.83433612888, 11775.1207182955, -8778.54790419679, 
16763.5123210592, 22848.6440740326, -6489.45689126298, 30800.6637732523, 
-551.847581456661, 7279.45757506074, 16553.5581036666, 24409.386796622, 
5000, 17034.95391905, 5911.25895762224, -3398.72060945524, -5768.19233706395, 
-4229.26594477481, 950.591089955921, 7113.20257251212, 15169.824261434, 
22845.3082603497, 5000, 17891.8984213341, 8496.55048880409, 1825.0696233992, 
810.028458075569, 3664.46564696929, 9709.21329815228, 17181.6765053446, 
22541.7047456193, 30057.7224595685, 5000, 16700.9168772748, 5593.03555882925, 
-2028.86483622101, -3646.32279645239, -1390.78650754587, 3577.56347915891, 
10603.9041039838, 17054.8291388964, 26773.7977012179, 5000, 16911.2865317119, 
4351.23637322548, -4015.73034866028, -6232.44446398637, -3712.84274506375, 
5000, 2359.01911895682, 16271.017845393, 4051.80942790909, 8039.18908838504, 
-3610.89152153722, 16884.5029036251, -5676.15773655211, 25712.2367099925, 
-4665.32703289247, 412.058636915032, 6496.08536117356, 12056.8192481081, 
25196.0924424919, 5000, 5000, 17454.1772703328, 8784.9903045364, 
16988.3805436717, 1335.40690314268, 5602.61993021557, 33.5055585529097, 
-2752.26594141369, 2520.04689099037, -4055.48284139309, 7495.51047961483, 
-1815.14909163591, 13534.6185065575, 3103.40704263755, 20137.3308304375, 
8718.30106806019, 28860.9163843801, 13226.1318243537, 24435.473414727, 
5000, 14986.7334079756, 1963.39221417673, -6940.3422302652, -9813.92833778304, 
-7880.89152429566, -2511.70627165876, 4625.27308695974, 13963.5897385531, 
25573.7792637622, 5000, 14544.0594029155, 1288.5755470104, -8084.93019036526, 
-11010.6902443854, -10229.4751821274, -5698.06964960847, 313.772270393078, 
9143.73659148442, 5000, 20302.391059426, 15742.8926221643, 4785.77974475384, 
-3227.05858371389, -5963.33972439362, -3794.38377216149, 1743.03069812496, 
8236.30553623782, 18026.036903884, 28860.5795376896, 5000, 14063.4086450927, 
-100.982715766215, -10590.0647932601, -15364.77439809, -14794.3472963714, 
-10015.1083148604, -3488.57992395531, 8161.55971721804, 5000, 
18291.7427906892, 16016.2517314456, 7153.29022517982, -412.365245692974, 
-3676.77133255859, -2554.9191987889, 1686.46778305379, 7036.49053148479, 
15770.8403030132, 26816.3192030426, 5000, 15906.2432400211, 7051.67441999044, 
-331.3307031639, -3754.84464355008, -1842.66807512373, 3227.05908236969, 
9139.62986841704, 19304.0598981924, 27256.8698709522, 5000, 15029.5843404416, 
2072.10802012564, -7304.22739544598, -10871.623560221, -9351.91079687121, 
5000, -5171.31622384352, 15159.683395421, 3331.5498754522, 13170.5005332417, 
3439.19465496068, 24198.2911262617, -5110.78422514425, -7804.4774428497, 
-5286.78032597168, 598.077862841574, 8436.96826228419, 17198.7098708175, 
24298.5553779913, 5000, 14309.8331053745, 1187.21043394015, -9952.57083904184, 
-14619.5327439154, -13199.0421104398, -8319.63907272906, -1304.4230914884, 
5000, 7830.70031170482, 14202.2194212579, 17903.384502826, 1081.76102495543, 
-7991.80925287105, -10526.8865875028, -9045.63162101956, -3279.39975586326, 
5501.88648798074, 5000, 12875.6885153624, 22221.2837723756, 15576.9803361784, 
4068.25688407986, -4708.99256150513, -8143.14199133205, -6896.55918399797, 
-2126.50851131449, 5000, 5240.64004517348, 14270.8200003207, 
13852.1401402282, -43.0325928681349, 24717.1050645578, -9438.40619357209, 
-13048.8094569982, -12138.7875588, -7659.79060929531, -1865.33889993808, 
5697.82327541651, 18086.4511779268, 5000, 15597.3988001253, 5561.58301979492, 
-2869.06709333548, -6558.886699838, -5169.73695267938, -609.782078563235, 
5898.56506874382, 14533.9561760599, 25482.7350976753, 5000, 15478.4673313563, 
3977.87968483323, 5000, -5985.95325671427, 15928.4015865356, 
-10319.6145358865, -9649.23736134543, 5383.60374279049, -4647.06609976334, 
-2999.475898658, 2068.47353878321, -6359.12927662916, 10311.2253685776, 
-4693.84008808353, 25624.3550621041, 866.127801082878, 6646.1046514394, 
15431.0247384072, 24474.9603730814, 5000, 13788.5168543132, -1731.13227111806, 
-13000.2021399356, -17201.8194814945, -14884.8997553708, 5000, 
-8667.01989469544, 15377.1237562577, 681.163334032681, 3385.79944090265, 
11611.196820045, -4774.05117801588, 23388.6483093974, -6372.24086221351, 
-4842.14991237637, -743.021710592532, 5833.73755214678, 12121.1598384927, 
21003.4686145283, 5000, 15183.2494510295, 3030.07907708138, -5345.64249061941, 
5000, -9638.05284666594, 16259.0530459828, -7503.92337904484, 
-2226.27356766879, 7183.80537659084, 6455.8638736604, -727.603893341901, 
15671.3254651653, 24194.9838410333, -3835.34577700104, -2098.79256988853, 
3090.29391478019, 8349.55950088762, 5000, 15758.2877450559, 14831.1008157696, 
25658.9962972256, 1619.69881835626, -7338.88491608739, -9591.47146367816, 
-8056.12113669679, -3537.64482128395, 3608.27743432899, 12650.7747287784, 
22233.8478781338, 5000, 13656.7228400099, 2767.80445934938, -6464.6064825382, 
-11618.44866774, -10686.8447765554, -6408.30193258191, -656.056692611712, 
7422.09138358902, 18758.5390231977, 5000, 12045.3182515538, -3238.06323662127, 
-14529.8018209528, -19907.4191089837, 5000, -19596.7129005575, 
14036.9100757928, 5000, -14721.8012791421, 12262.9676244423, 
1531.66737285799, -7901.79936280156, -3377.97620455655, 3642.25418333018, 
-7688.5762733587, -15703.9233053286, 17896.7314709099, -12086.2394306819, 
-21366.6861860903, -19550.5471658072, -10930.6598354357, -14335.785648655, 
-6953.79895440406, -5638.00453480549, 5000, -1022.23761208204, 
5742.81522591873, 19206.177851139, 12966.6328737482, 8406.89466120168, 
22992.1412638757, -890.590811647627, 5000, -10209.6954754654, 
14198.0363268739, -13408.9055093147, 3311.06607469565, -11240.5141564193, 
-4982.80509003836, -5677.65928846774, -8537.90872063919, 239.368339089975, 
-7662.81690858933, 10870.7617155271, -3759.30275900418, 2137.10949487681, 
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If I plot that :

library(ggplot2)
bp_capital_lt<-ggplot(data=a)+
  geom_boxplot(aes(as.factor(X.step.),Capital_Hill))+
  labs(list(x = "itérations", y = "capital"))
bp_capital_lt

I can have something like this:

But I would like to have only 0 2 4 6 8 in x-axis ...

I have tried something like

sel<-a$X.step.==seq(2,10,by=2)
bp_capital_lt<-ggplot(data=a[sel,])+
  geom_boxplot(aes(as.factor(X.step.),Capital_Hill))+
  labs(list(x = "itérations", y = "capital"))
bp_capital_lt

But it doesn't work like what I expect! What is wrong? How can I do?

Thank you

E

Answer 1

You can create a subset of the data in which all values of X.step. are divisible by 2.

a2 <- subset(a, ! X.step. %% 2)

This subset can be used for the plot.

library(ggplot2)
ggplot(data = a2) +
  geom_boxplot(aes(as.factor(X.step.), Capital_Hill)) +
  labs(list(x = "itérations", y = "capital"))