Label subset of data points in QQ plot-CodePudding

I'm trying to generate a QQ plot where I would like to label the respective points.

This is my data subset

dput(head(C_A,10))
structure(list(CONTROL_ASYMPTOMATIC = structure(c(3L, 4L, 1L, 
53L, 5L, 11L, 35L, 31L, 20L, 45L), .Label = c("Acidocella.facilis", 
"Cellulosimicrobium.cellulans", "Citrobacter.freundii", "Citrobacter.koseri", 
"Gallibacterium.anatis", "Mycobacterium.asiaticum", "Mycobacterium.avium", 
"Mycobacterium.cookii", "Mycobacterium.gastri", "Mycobacterium.gordonae", 
"Mycobacterium.hyorhinis", "Mycobacterium.intracellulare", "Mycobacterium.kansasii", 
"Mycobacterium.leprae", "Mycobacterium.malmoense", "Mycobacterium.marinum", 
"Mycobacterium.scrofulaceum", "Mycobacterium.simiae", "Mycobacterium.sp.", 
"Mycobacterium.szulgai", "Mycobacterium.tuberculosis", "Mycobacterium.ulcerans", 
"Mycobacterium.xenopi", "Mycobacteroides.chelonae", "Mycolicibacillus.trivialis", 
"Mycolicibacterium.aichiense", "Mycolicibacterium.aurum", "Mycolicibacterium.chitae", 
"Mycolicibacterium.chubuense", "Mycolicibacterium.diernhoferi", 
"Mycolicibacterium.fallax", "Mycolicibacterium.farcinogenes", 
"Mycolicibacterium.flavescens", "Mycolicibacterium.fortuitum", 
"Mycolicibacterium.gadium", "Mycolicibacterium.gilvum", "Mycolicibacterium.komossense", 
"Mycolicibacterium.neoaurum", "Mycolicibacterium.obuense", "Mycolicibacterium.phlei", 
"Mycolicibacterium.senegalense", "Mycolicibacterium.smegmatis", 
"Mycolicibacterium.sphagni", "Mycolicibacterium.thermoresistibile", 
"Mycolicibacterium.vaccae", "Mycoplasma.agalactiae", "Mycoplasma.capricolum", 
"Mycoplasma.hyorhinis", "Mycoplasma.neurolyticum", "Mycoplasma.pneumoniae", 
"Mycoplasma.salivarium", "Oerskovia.turbata", "Orientia.tsutsugamushi", 
"Streptosporangium.amethystogenes"), class = "factor"), p_value = c(7.75e-07, 
7.83e-07, 1.72e-06, 2.89e-05, 0.000133449, 0.000419124, 0.000422792, 
0.000452307, 0.000726928, 0.000914429)), row.names = c(NA, 10L
), class = "data.frame")

To generate the QQ Plot

My code

loc <- qqnorm(C_A$p_value, ylim = extendrange(C_A$p_value, f = 0.05))

text(loc[[1]], loc[[2]], C_A$CONTROL_ASYMPTOMATIC, pos = 3)

Is there any way to improve the labeling such as only those points which have the highest significance.

Any suggestion or help would be really appreciated

CodePudding user response：

Subset significant ones when adding the text:

#plot dots
loc <- qqnorm(C_A$p_value, ylim = extendrange(C_A$p_value, f = 0.05))

#get the index of significant points
#note: I am using 0.00001 as significant,
# amend this number as per your needs.
ix <- which(C_A$p_value < 0.00001)

#subset and add text
text(loc[[1]][ ix ], loc[[2]][ ix ], 
     C_A$CONTROL_ASYMPTOMATIC[ ix ], pos = 4, srt = 90)