How to convert in a string a dataframe to fix an error to plot properly some graphs?-CodePudding

I'm trying plotting some graphs via the following loop:

library(ggstatsplot)
for (i in 5:ncol(df_join)) {
  print(ggbetweenstats(df_join,
                       x = 'COND', y = colnames(df_join[i]),
                       palette = 'npg', 
                       effsize.type = 'eta', 
                       type = "parametric", # ANOVA or Kruskal-Wallis
                       var.equal = TRUE, # ANOVA or Welch ANOVA
                       plot.type = "box",
                       pairwise.comparisons = TRUE,
                       pairwise.display = "significant",
                       centrality.plotting = FALSE, 
                       bf.message = FALSE
    ))
}

However I'm keeping on getting back this error warning message:

Error: Only strings can be converted to symbols

For ensurance, I post below the dataset I'm working on:

head(dput(df_join))
structure(list(ID = c("01", "01", "01", "04", "04", "04", "06", 
"06", "06", "07", "07", "07", "08", "08", "08", "09", "09", "09", 
"10", "10", "10", "11", "11", "11", "12", "12", "12", "13", "13", 
"13", "15", "15", "15", "16", "16", "16", "17", "17", "17", "18", 
"18", "18", "19", "19", "19", "21", "21", "21", "22", "22", "22", 
"23", "23", "23", "25", "25", "25", "27", "27", "27", "28", "28", 
"28", "30", "30", "30", "44", "44", "44", "46", "46", "46", "49", 
"49", "49"), GR = c("RP", "RP", "RP", "RP", "RP", "RP", "RP", 
"RP", "RP", "RP", "RP", "RP", "RP", "RP", "RP", "RP", "RP", "RP", 
"RP", "RP", "RP", "RP", "RP", "RP", "RP", "RP", "RP", "RP", "RP", 
"RP", "RP", "RP", "RP", "RP", "RP", "RP", "RP", "RP", "RP", "RP", 
"RP", "RP", "RP", "RP", "RP", "RP", "RP", "RP", "RP", "RP", "RP", 
"RP", "RP", "RP", "RP", "RP", "RP", "RP", "RP", "RP", "RP", "RP", 
"RP", "RP", "RP", "RP", "RP", "RP", "RP", "RP", "RP", "RP", "RP", 
"RP", "RP"), SES = c("V", "V", "V", "V", "V", "V", "V", "V", 
"V", "V", "V", "V", "V", "V", "V", "V", "V", "V", "V", "V", "V", 
"V", "V", "V", "V", "V", "V", "V", "V", "V", "V", "V", "V", "V", 
"V", "V", "V", "V", "V", "V", "V", "V", "V", "V", "V", "V", "V", 
"V", "V", "V", "V", "V", "V", "V", "V", "V", "V", "V", "V", "V", 
"V", "V", "V", "V", "V", "V", "V", "V", "V", "V", "V", "V", "V", 
"V", "V"), COND = structure(c(1L, 2L, 3L, 1L, 2L, 3L, 1L, 2L, 
3L, 1L, 2L, 3L, 1L, 2L, 3L, 1L, 2L, 3L, 1L, 2L, 3L, 1L, 2L, 3L, 
1L, 2L, 3L, 1L, 2L, 3L, 1L, 2L, 3L, 1L, 2L, 3L, 1L, 2L, 3L, 1L, 
2L, 3L, 1L, 2L, 3L, 1L, 2L, 3L, 1L, 2L, 3L, 1L, 2L, 3L, 1L, 2L, 
3L, 1L, 2L, 3L, 1L, 2L, 3L, 1L, 2L, 3L, 1L, 2L, 3L, 1L, 2L, 3L, 
1L, 2L, 3L), .Label = c("NEG-CTR", "NEG-NOC", "NEU-NOC"), class = "factor"), 
    P3FCz = c(-11.6312151716924, -11.1438413285935, -3.99591470944713, 
    -0.314155675382471, 0.238885648959708, 5.03749946898385, 
    -0.213621915029167, -2.96032491743069, -1.97168681693488, 
    -2.83109425298642, 1.09291198163802, -6.692991645215, 4.23849942428043, 
    2.9898889629932, 3.5510699900835, 9.57481668808606, 5.4167795618285, 
    1.7067607715475, -6.13036076093477, -2.82955734597919, -2.50672211111696, 
    0.528517585832501, 8.16418133488309, 1.88777321897925, -7.73588468896919, 
    -9.83058052401056, -6.97442700196932, 1.27327945355082, 2.11962397764132, 
    0.524299677616254, -1.83310726842883, 0.658810483381172, 
    -0.261373488428192, 4.37524298634374, 0.625555654900511, 
    3.19617639836154, 0.0405517582137798, -3.29357103412113, 
    -0.381435057304614, -5.73445509910268, -6.1129152355645, 
    -2.45744234877604, 2.95352732001065, 0.527721249096473, 1.91803490989119, 
    -3.46703346467546, -2.40438419043702, -5.35374408162217, 
    -7.27028665849262, -7.1532211375959, -5.39955520296854, 2.65765002364624, 
    0.372495441513391, 6.24433066412776, 1.85698518142405, -0.564454675803529, 
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    -4.36762718685405, -6.71005969834916, -4.22719611676328, 
    -0.229916506217565, -5.69725200870146), P3Cz = c(-5.16524399006139, 
    -5.53112490175437, 0.621502123415388, 2.23100741241039, 3.96990710862955, 
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    -4.48258340054462, -1.42281778522059, 2.62315679073783, -4.13736508533355
    ), P3Pz = c(11.8802266972569, 12.1053426662461, 12.955441582096, 
    15.0981004360619, 15.4046229884164, 16.671036999147, 3.13771453335467, 
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    14.3862738306396, 6.86762877785576, 7.47946451329025, 8.93405130318593, 
    8.45962311067909, 23.4166601996042, 15.1868092142896, 9.97183712753913, 
    6.267521071803, 10.142198458411, 10.6320358418368, 12.9998037913548, 
    20.7052065690674, 11.8852179570666, 15.7899796085713, 7.50729833890206, 
    14.3076172484818, 9.93797956768228, 10.7693238464384, 5.04681800218272, 
    5.16656503460515, 7.87875085817396, 2.29899409536951, 10.0135486953849, 
    5.48278706243332, 7.81908431468528, 8.64382513728869, 3.35777109534179, 
    3.47474629234488, 4.35678644331281, 3.47085321062162, 6.56231512354717, 
    4.93825547529124, 7.33985613752315, 6.81966900599588, 6.54487921689425, 
    7.25872117706077, 1.10301223694429, -0.856423579793706, -0.887835692028378, 
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    6.59026080217083, 3.0741733363644, 1.80359068950898, 1.63892755704177, 
    3.857933716935, 0.769316188513939, 10.7031907391191, 9.53278894637555, 
    8.01071628743378, 6.04891324234645, 11.1964453850602, 3.46633322373091, 
    14.4393884282958, 11.2339563353478, 7.74933708914689, 7.1182095475238, 
    7.39260082121406, 0.627435381320771, 9.15473202689768, 13.6559037433263, 
    7.14786907480758), LPPearlyFCz = c(-11.7785042972793, -9.14927207125904, 
    -7.58190508537766, -4.01515836011381, -6.60165385653499, 
    -2.02861964460179, 4.46729570509601, 2.54036572774646, 2.22923889930115, 
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    -0.856727109535223, -1.16182571974245, 1.07658425742917, 
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    -0.888293709383838, -2.14177059335841, -2.42141595261389, 
    -2.958120275175, -5.1274001953303, -5.32347488769128, -4.41290818553442, 
    -1.21404719262173, -4.23649270310915), LPPearlyCz = c(-5.96429031525769, 
    -5.10918437158799, -2.81732229625975, -1.43557366487622, 
    -3.14872157912645, 0.160393685024631, 3.52155765271648, 2.10437989449921, 
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    4.19096721581768, 0.815283302847055, 1.48137456347872, 2.0809543999959, 
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    -2.61585906518491, -2.71685194532693, -1.7348388034111, 1.00287124847525, 
    -2.4844653851482), LPPearlyPz = c(8.23981597718437, 9.51261484648731, 
    9.42367409925817, 5.06332653216481, 5.02619159395405, 9.07903916629231, 
    7.56089165217984, 5.49719893790597, 4.91476855238182, 13.0320953572069, 
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    2.02262615478956, 1.0510618938653, 5.62233873107127, 10.1193593084848, 
    5.87476640145049), LPP1FCz = c(-5.67295796971287, -4.3918290080777, 
    -2.96652960658775, 0.159183652691071, -1.78361184935376, 
    1.97377908783621, 3.17401220482225, 1.60211665164145, 2.27932356239417, 
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    -4.99161397741678, -2.08242541523686, -0.770668513084632, 
    -2.90677423807339), LPP1Cz = c(-0.774461731301161, -0.650009462761383, 
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    -0.080319620782262, 1.67927888371665, -1.30897538037428), 
    LPP1Pz = c(9.99385579756163, 11.1212652173052, 10.6989716871958, 
    3.7899021820967, 4.59413830322224, 8.52123662617732, 6.34418311104072, 
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    -0.385577376783475, 5.16871756657453, 8.83562199570849, 5.14162645294768
    ), LPP2FCz = c(-0.198736254963744, -3.16101041766438, 0.895992279831378, 
    3.11042068112836, 2.27800090558473, 3.83846437952292, 0.70169995101623, 
    1.75290674648806, -1.33916628569866, 6.69246804853767, 4.76363910849669, 
    5.6387334295083, 1.37744267413711, 0.973396686787801, 1.98775658048965, 
    4.70492544977759, 12.1173859570715, 1.04588866129981, -3.27424811388479, 
    3.17906097432267, -0.737029533303028, -0.548079192716476, 
    4.61956745266038, 2.83406431170166, -2.03662250850588, -1.04583230182887, 
    -4.10197843548265, 1.74578985593211, 0.337182270006865, 1.0088582830766, 
    4.7071611424039, 2.91357065338633, 3.41865997847206, 0.112840808931107, 
    3.65320446800974, 1.68471621974079, -1.0319619837514, -1.20400880603756, 
    -0.36155713377909, -3.37172556803734, -4.73982223428082, 
    0.276424687829489, 5.00204428574547, 2.59240054429885, 1.76823718363874, 
    2.89875624368901, 3.26725194423518, 1.68068636794087, 5.10788499683596, 
    10.9438273543919, 8.57093653637002, 4.13801289432792, -0.0919103435752493, 
    7.14602235806343, 0.951033896893375, -3.50828531999296, -0.245809508894366, 
    3.74570635774348, 3.35958383952017, 0.585956207256955, -0.953752628300353, 
    0.198016547101522, -1.52627773487111, -2.5380125964518, -3.87040246779716, 
    -3.39003001417816, -0.0562425891448048, -1.93150124231358, 
    0.14533441948593, -6.30600497325119, -4.05937234925567, -5.38510065662888, 
    3.42195795553968, 4.06645814493399, 1.56160375018352), LPP2Cz = c(2.96437294922766, 
    -2.12913230708907, 2.94619035115619, 3.44844607014521, 3.02403433835637, 
    4.7045767546583, -0.119440173019054, 0.668265457194833, -0.405630185540259, 
    7.32640154038155, 6.75063445570149, 1.59973104216962, 0.716894061961362, 
    1.15587576192688, -0.0113614476558772, 6.44896958389742, 
    10.5178519351064, 3.79329103591037, -0.881527211868382, 4.99936090838488, 
    0.547336389166803, 0.914180881345654, 4.57223746317305, 0.544379787211248, 
    2.10232992003589, 0.364087929362296, -2.01625839730052, 2.92045510618672, 
    0.589250314392448, 2.47669253216776, 3.8646810953732, 1.39548469719622, 
    3.99379121188326, -2.43380575479143, 3.55543459632094, 1.8064338549701, 
    1.32843479186238, 0.998168707936746, 2.22142205600503, -2.57872703851591, 
    -2.47010661770972, 3.56904822058867, 6.29976121968667, 4.17893812674545, 
    2.05354063483883, 2.80516686935069, 5.94481009988668, 2.24420650476028, 
    3.87077739797244, 7.51898916194332, 8.04385138833399, -0.837752514082802, 
    -0.472475810660207, 3.94854087847063, 1.42192692667874, 0.41259599596416, 
    -1.26656454994214, 3.70559987919106, 4.95053154685134, 1.54527082821889, 
    -2.35132492869438, 1.27825568281823, -1.87474139426298, -4.61839904975041, 
    -2.75088839785752, -4.54674069848035, 0.707894602445896, 
    -2.39741431959044, 1.06029338143336, -4.65014144483362, -3.37506398767823, 
    -4.32939541342964, 3.99189974753945, 5.66199164861177, 3.38297407425817
    ), LPP2Pz = c(6.28027312932027, 5.24535230966772, 7.68162285335806, 
    1.08242973465635, 2.99896314000211, 5.36085942954182, 1.22060069796986, 
    0.43007709818575, 0.476667611076957, 8.73650967214853, 7.20593389743811, 
    4.57722295263921, -1.33620384654018, -1.28885901608471, -0.547579465083117, 
    8.11715753014206, 13.3060153720352, 2.03237948843614, 2.88799699943079, 
    5.57921718107867, 0.224312643096751, -1.35508717090199, 5.24004334238142, 
    -0.524427185444798, 9.53009273459153, 5.96824937367958, 0.354581513905486, 
    3.75491412513142, 1.62293479252637, 1.13298849399454, 1.3038251300445, 
    2.21921258546698, -0.982935199970812, -0.87603278792859, 
    4.07313151833664, 2.67697914555442, 2.01133614153975, 0.713386363228727, 
    1.82011380148253, -2.14054013397946, -2.91688430317331, 3.4064978775436, 
    6.970012019096, 4.8346929061964, 4.05060374186422, 3.15582202707403, 
    6.30033458860474, 1.54086695776033, 4.70486363207892, 7.02302307690502, 
    4.86622757700525, 0.519683704125285, 3.22734666260273, 2.66173787497657, 
    -1.38695689767217, -1.01240056675658, -2.24262472628189, 
    6.00477421965019, 4.20438929142231, 1.13798685231667, -0.897086547028692, 
    2.0228708306979, -0.589472259038692, -0.204119654251134, 
    1.34241259142242, 1.9188582401756, 3.75503694959562, 2.11369999794381, 
    2.2112162248386, -2.7719104342547, -3.28212379920159, -2.66041249378004, 
    4.4514507366784, 8.01351241284005, 8.18987741895779)), row.names = c(NA, 
-75L), class = "data.frame")

I'm not sure whether I should convert the dataset I'm working on into a string for fixing this problem. Is there anyone that can explain and show how to fix it?

CodePudding user response：

The code has been smartly written to work if you pass bare column names.

library(ggstatsplot)

ggbetweenstats(df_join,x = COND, y = P3FCz)

Or column names as strings.

ggbetweenstats(df_join,x = 'COND', y = 'P3FCz')

But it returns an error when you pass column names as variables.

a <- 'COND'
b <- 'P3FCz'

ggbetweenstats(df_join,x = a, y = b)

Error: Can't subset columns that don't exist. x Column a doesn't exist.

It would work if you force the evaluation of the variables with !!.

a <- 'COND'
b <- 'P3FCz'

ggbetweenstats(df_join,x = !!a, y = !!b)

So in your for loop you may use -

for (i in 5:ncol(df_join)) {
  print(ggbetweenstats(df_join, x = 'COND', y = !!colnames(df_join[i])))
}