r - ggplot2 geom_errorbar in reshaped data -

in data.frame appended trend device sensitivity @ 2 distances measurement t date, facetted monitor. pretty straightforward in ggplot2. first melt data usinge reshape2 package

data.melt <- melt(big_df[,c(1:3,6)],id=c("date","monitor")) 

then use ggplot2

ggplot(data.melt, aes(x=date, y=value, col=variable)) + geom_point() + facet_wrap(~monitor) 

i add geom_errorbar these points. problem have error bars differ 50cm , 100cm measurements , unsure how define limits. i.e if variable = sensitivity.100cm set limits value+/-error.100cm , variable = sensitivity.50cm limits = value+/-error.50cm. how can best approach task?

structure(list(date = c("18/10/2012", "19/10/2012", "22/10/2012",  "23/10/2012", "23/10/2012", "26/10/2012", "29/10/2012", "31/10/2012",  "11/01/2012", "11/02/2012", "11/06/2012", "11/08/2012", "11/09/2012",  "20/11/2012", "27/11/2012", "18/12/2012", "14/01/2012", "23/01/2013",  "18/01/2013", "16/02/2013", "23/04/2013", "30/04/2013", "07/05/2013",  "14/05/2013", "21/05/2013", "17/10/2012", "18/10/2012", "19/10/2012",  "22/10/2012", "23/10/2012", "24/10/2012", "26/10/2012", "29/10/2012",  "31/10/2012", "11/01/2012", "11/02/2012", "11/06/2012", "11/08/2012",  "11/09/2012", "20/11/2012", "27/11/2012", "18/12/2012", "14/01/2013",  "23/01/2013", "18/02/2013", "16/02/2013", "14/04/2013", "30/04/2013",  "07/05/2013", "14/05/2013", "21/05/2013", "16/10/2012", "18/10/2012",  "19/10/2012", "22/10/2012", "23/10/2012", "24/10/2012", "26/10/2012",  "29/10/2012", "31/10/2012", "31/10/2012", "01/11/2012", "02/11/2012",  "06/11/2012", "08/11/2012", "09/11/2012", "20/11/2012", "27/11/2012",  "18/12/2012", "14/01/2013", "23/01/2013", "18/02/2013", "16/04/2013",  "23/04/2013", "30/04/2013", "07/05/2013", "14/05/2013", "21/05/2013",  "16/04/2013", "23/04/2013", "30/04/2013", "07/05/2013", "14/05/2013",  "21/05/2013", "16/04/2013", "23/04/2013", "30/04/2013", "07/05/2013",  "14/05/2013", "21/05/2013"), sensitivity.100cm = c(23.9310344827586,  23.6792452830189, 23.0708661417323, 23.75, 31.3333333333333,  25.1351351351351, 25.9770114942529, 24.5192307692308, 25.4347826086957,  22.987012987013, 23.1451612903226, 22.4822695035461, 23.4375,  23.9495798319328, 23.5245901639344, 24.041095890411, 25.4198473282443,  23.9097744360902, 25.8536585365854, 26.1940298507463, 28.0794701986755,  26.4041095890411, 24.3875968992248, 24.7019867549669, 26.4383561643836,  21.2328767123288, 23.5172413793103, 24.0566037735849, 30.7874015748032,  23.1111111111111, 29.5, 23.0405405405405, 26.2068965517241, 25,  24.3478260869565, 23.5064935064935, 22.0161290322581, 23.468085106383,  22.8125, 25.3781512605042, 22.2131147540984, 24.7945205479452,  23.6923076923077, 24.1353383458647, 25.2439024390244, 26.9402985074627,  27.9470198675497, 23.8835616438356, 25.3798449612403, 25.0331125827815,  25.7534246575342, 31.1627906976744, 30.6896551724138, 28.7735849056604,  29.7637795275591, 28.5294117647059, 40, 29.7972972972973, 33.448275862069,  33.4653465346535, 33.4653465346535, 36.9565217391304, 31.4285714285714,  30.8870967741935, 28.5106382978723, 29.0625, 29.4117647058824,  31.3934426229508, 33.5616438356164, 29.0151515151515, 30.8270676691729,  29.6341463414634, 34.3283582089552, 32.7152317880795, 37.2602739726027,  38.2945736434108, 35.8940397350993, 33.5616438356164, 40.5223880597015,  36.0264900662252, 33.8356164383562, 34.4186046511628, 36.158940397351,  33.7671232876712, 36.7910447761194, 36.0264900662252, 33.8356164383562,  30.5426356589147, 36.158940397351, 33.7671232876712), sensitivity.50cm = c(89.448275862069,  89.4339622641509, 88.0314960629921, 88.4558823529412, 94.6666666666667,  85.9459459459459, 92.2988505747126, 93.6538461538461, 91.5217391304348,  88.2467532467532, 98.1451612903226, 85.6028368794326, 88.28125,  90, 85.655737704918, 87.7397260273973, 88.7786259541985, 90.8270676691729,  92.1341463414634, 89.6268656716418, 96.6887417218543, 91.1986301369863,  89.7364341085271, 87.0198675496689, 90.4794520547945, 80.8219178082192,  83.8620689655172, 85.188679245283, 82.992125984252, 88.1481481481482,  93.3333333333333, 87.9054054054054, 90.6896551724138, 89.3269230769231,  89.1304347826087, 90.1298701298701, 82.9032258064516, 82.6879432624114,  87.265625, 88.8235294117647, 87.7868852459016, 90.5479452054795,  91.7692307692308, 83.5338345864662, 92.0121951219512, 94.1044776119403,  88.0132450331126, 90.8013698630137, 89.7984496124031, 87.6158940397351,  88.2191780821918, 116.434108527132, 110, 116.509433962264, 112.44094488189,  110.147058823529, 123.333333333333, 107.5, 119.655172413793,  127.524752475248, 127.524752475248, 118.478260869565, 96.3636363636364,  112.338709677419, 105.815602836879, 116.5625, 116.806722689076,  118.27868852459, 129.452054794521, 113.106060606061, 115.789473684211,  115, 133.582089552239, 132.05298013245, 136.575342465753, 154.573643410853,  118.675496688742, 122.602739726027, 133.805970149254, 132.05298013245,  136.575342465753, 154.573643410853, 132.185430463576, 136.506849315069,  133.805970149254, 132.05298013245, 136.575342465753, 154.573643410853,  132.185430463576, 136.506849315069), error.100cm = c(1.3139695781557,  1.56444565582802, 1.40192864683188, 1.36970117722038, 1.67497927018681,  1.33092672997245, 1.78068199825628, 1.60608587389328, 1.71862916313499,  1.29219147676184, 1.40378186980074, 1.29420479368047, 1.39754248593737,  1.46276430130498, 1.42679468733846, 1.31571045974648, 1.42197984810665,  1.39046932397796, 1.30208271366236, 1.4335352770372, 1.39230437361779,  1.37754694254238, 1.41544528946403, 1.3095178763765, 1.37669529056451,  1.81215843223602, 1.30671002217217, 1.60377358490566, 1.7304929902233,  1.34969386357693, 1.63724022536571, 1.28022265685787, 1.79545969561073,  1.60896158948861, 1.69788036432753, 1.30840530387077, 1.36621567307237,  1.32512183966048, 1.37108818553002, 1.49853399160731, 1.39344262295082,  1.33165904761805, 1.38033526499434, 1.40462719490747, 1.28772634645993,  1.45283002492028, 1.38599003552691, 1.31267619160706, 1.44319351564034,  1.32118790352715, 1.35955022200543, 1.5848874651365, 1.47108475915183,  1.72669860544558, 1.61753059717907, 1.49248405369003, 1.86338998124982,  1.44758684362355, 2.02050526795942, 1.88379184063767, 1.88379184063767,  2.06235499576199, 1.47504112877929, 1.60684345525575, 1.45000342555042,  1.53888403153064, 1.61641882871188, 1.63318515124355, 1.54679312200496,  1.50945900342207, 1.55913092882163, 1.38241268887252, 1.63499270897065,  1.48969826214596, 1.61504467432214, 1.74375533010884, 1.56437242530036,  1.54679312200496, 1.76125727182178, 1.56156637384789, 1.54071532591808,  1.65536096930718, 1.55875527098541, 1.54223702043804, 1.68034779838772,  1.56156637384789, 1.54071532591808, 1.56197222322557, 1.55875527098541,  1.54223702043804), error.50cm = c(2.49898909406806, 2.94121835247545,  2.66090476357729, 2.57562939531426, 2.84312035153866, 2.42491330336843,  3.28542665010493, 3.03760942287141, 3.183873590408, 2.43051523015752,  2.83178223646443, 2.48024233333982, 2.64934764965831, 2.77310924369748,  2.66991761883645, 2.46860565629316, 2.61888806082572, 2.63908703380214,  2.39518528553687, 2.6055358582233, 2.54601096513127, 2.51706504452232,  2.65881302492679, 2.41699173389333, 2.50632526897698, 3.38331206444616,  2.42264387175866, 2.88777884245547, 2.66556076847414, 2.57667068606312,  2.82842712474619, 2.45392159423444, 3.26120941588761, 2.96210034629795,  3.15029929264988, 2.45725817252266, 2.60322780509177, 2.44047901652299,  2.62969260620419, 2.75266207632928, 2.70491803278689, 2.50538919974957,  2.67245427169849, 2.53752436551672, 2.39363249102323, 2.66888876749965,  2.42875772462149, 2.51128061073898, 2.6601687552902, 2.42695128500777,  2.47524808213598, 3.02027282771754, 2.76292767227726, 3.35536212146769,  3.02099623515762, 2.86858958869576, 3.22748612183951, 2.71029339461238,  3.74049197592482, 3.5862911438168, 3.5862911438168, 3.62137635846906,  2.52830160180932, 3.02499989250178, 2.75411175020533, 3.03382622483556,  3.15545938748212, 3.12874339081841, 2.99339361416605, 2.94091650663359,  2.96968686588444, 2.66763937246675, 3.1749324456989, 2.96611863265678,  3.06769803788475, 3.47196832194708, 2.81593266562507, 2.91397909399762,  3.17230019504959, 2.96611863265678, 3.06769803788475, 3.47196832194708,  2.96463964047674, 3.06846257323317, 3.17230019504959, 2.96611863265678,  3.06769803788475, 3.47196832194708, 2.96463964047674, 3.06846257323317 ), monitor = c("berthold red", "berthold red", "berthold red",  "berthold red", "berthold red", "berthold red", "berthold red",  "berthold red", "berthold red", "berthold red", "berthold red",  "berthold red", "berthold red", "berthold red", "berthold red",  "berthold red", "berthold red", "berthold red", "berthold red",  "berthold red", "berthold red", "berthold red", "berthold red",  "berthold red", "berthold red", "berthold blue", "berthold blue",  "berthold blue", "berthold blue", "berthold blue", "berthold blue",  "berthold blue", "berthold blue", "berthold blue", "berthold blue",  "berthold blue", "berthold blue", "berthold blue", "berthold blue",  "berthold blue", "berthold blue", "berthold blue", "berthold blue",  "berthold blue", "berthold blue", "berthold blue", "berthold blue",  "berthold blue", "berthold blue", "berthold blue", "berthold blue",  "nc 61", "nc 61", "nc 61", "nc 61", "nc 61", "nc 61", "nc 61",  "nc 61", "nc 61", "nc 61", "nc 61", "nc 61", "nc 61", "nc 61",  "nc 61", "nc 61", "nc 61", "nc 61", "nc 61", "nc 61", "nc 61",  "nc 61", "nc 61", "nc 61", "nc 61", "nc 61", "nc 61", "mini red",  "mini red", "mini red", "mini red", "mini red", "mini red", "mini blue",  "mini blue", "mini blue", "mini blue", "mini blue", "mini blue" )), .names = c("date", "sensitivity.100cm", "sensitivity.50cm",  "error.100cm", "error.50cm", "monitor"), class = "data.frame", row.names = c(na,  90l)) 

library(reshape2) data.melt <- melt(big_df[,c(1:3,6)],id=c("date","monitor")) data.melt2 <- melt(big_df[,c(1,4:6)],id=c("date","monitor"))  levels(data.melt2$variable) <- levels(data.melt$variable)  data.melt <- merge(data.melt,data.melt2,by=c("date","monitor","variable"))  library(ggplot2) ggplot(data.melt, aes(x=date, y=value.x, col=variable)) +    geom_point() +    geom_errorbar(aes(ymin=value.x-value.y,ymax=value.x+value.y)) +   facet_wrap(~monitor)