Replace a certain number with a phrase in R - r

I have a data.frame that looks like
SNP CHR BP A1 A2 EFF SE P NGT
rs882982 1 100066094 a g -.0179 .006 .002797 28 .486
rs7518025 2 100066515 t c .0198 .0059 .0007438 26 .47
rs6678322 3 100069554 a t .0187 .0059 .001498 25 .452
rs61784986 14 100074953 t c -.0182 .0058 .001748 26 .469
rs7554246 21 100075695 t c -.0167 .006 .004932 26 .455
rs12121193 16 100075777 a t -.0183 .0058 .001652 26 .471
rs835016 3 100078102 t c .02 .0065 .001979 28 .196
And I would like to add the letters "chr" before the numbers in the CHR column. My desired output is:
SNP CHR BP A1 A2 EFF SE P NGT
rs882982 chr1 100066094 a g -.0179 .006 .002797 28 .486
rs7518025 chr2 100066515 t c .0198 .0059 .0007438 26 .47
rs6678322 chr3 100069554 a t .0187 .0059 .001498 25 .452
rs61784986 chr14 100074953 t c -.0182 .0058 .001748 26 .469
rs7554246 chr21 100075695 t c -.0167 .006 .004932 26 .455
rs12121193 chr16 100075777 a t -.0183 .0058 .001652 26 .471
rs835016 chr3 100078102 t c .02 .0065 .001979 28 .196
Should I use grep somehow, or what are some useful R commands?

Just use paste():
df$CHR <- as.character(df$CHR) # in case it is a factor column
df$CHR <- paste("chr", df$CHR, sep="")

Related

How to generate z-scores separately for each factor level using a loop in R?

I would like to convert variable to z-scores. How to do that for each factor cell level separately using a loop?
Example DATA:
df = data.frame(Cell = c(rep("13a",5),rep("1b",5),rep("5b",5)),
condition = rep(c("a","b","c","d","e"),3),
variable = c(58,55,36,29,53,57,53,54,52,52,45,49,48,46,45))
Is this a good start?... Maybe the loop is not necessary buy I would like to learn how to write loops...
# Final data frame containing the results of all loops
df_z = data.frame()
# Loop through by cell
for (i in 1:unique(df$Cell)) {
df_z$myZ <- scale(variable)
}
It can be done with a group_by operation
library(dplyr)
df %>%
group_by(Cell) %>%
mutate(myZ = as.numeric(scale(variable)))
Or with data.table
library(data.table)
setDT(df)[, myZ := as.numeric(scale(variable)), by = Cell][]
In the case for for loop, we can subset the in each of the iteration and assign the scaled values to the created 'myZ' variable
un1 <- unique(df$Cell)
df$myZ <- NA
for(un in un1) {
i1 <- df$Cell == un
df$myZ[i1] <- as.numeric(scale(df$variable[i1]))
}
Or with split
df$myZ <- unsplit(lapply(split(df$variable, df$Cell), scale), df$Cell)
We can use ave in base R :
df$myZ <- with(df, ave(variable, Cell, FUN = scale))
df
# Cell condition variable myZ
#1 13a a 58 0.917
#2 13a b 55 0.684
#3 13a c 36 -0.792
#4 13a d 29 -1.336
#5 13a e 53 0.528
#6 1b a 57 1.640
#7 1b b 53 -0.289
#8 1b c 54 0.193
#9 1b d 52 -0.772
#10 1b e 52 -0.772
#11 5b a 45 -0.881
#12 5b b 49 1.321
#13 5b c 48 0.771
#14 5b d 46 -0.330
#15 5b e 45 -0.881

return a vector in a column in data.table

I have a data.table in R, and I'm looking to create a vector based on .SDcols row by row.
library("data.table")
dt = data.table(
id=1:6,
A1=sample(100,6),
A2=sample(100,6),
A3=sample(100,6),
B1=sample(100,6),
B2=sample(100,6),
B3=sample(100,6)
)
dt[,x1:=paste(.SD,collapse = ","),.SDcols=A1:B3,by=id]
dt[,x2:=strsplit(x1,",")] # x2 vector of characters
now, I got x2 with a vector of characters.
however, I expected x2 with a vector of integers.
R > dt
id A1 A2 A3 B1 B2 B3 x2
1: 1 72 23 76 10 35 14 c(72,23,76,10,35,14)
2: 2 44 28 77 29 20 63 c(44,28,77,29,20,63)
3: 3 18 34 43 77 76 100 c(18,34,43,77,76,100)
4: 4 15 33 50 87 86 86 c(15,33,50,87,86,86)
5: 5 71 71 41 75 8 3 c(71,71,41,75,8,3)
6: 6 11 89 98 42 72 27 c(11,89,98,42,72,27)
I tried with several solutions, all failed.
dt[,x2:=.(list(.SD)),.SDcols=A1:B3,by=id] #x2 is <data.table>
dt[,x2:=.(lapply(.SD,c)),.SDcols=A1:B3,by=id]
dt[,x2:=.(c(.SD)), .SDcols=A1:B3,by=id] #RHS 1 is length 6 (greater than the size (1) of group 1). The last 5 element(s) will be discarded.
dt[,x2:=c(.SD),.SDcols=A1:B3,by=id] # x2 equals A1
dt[,x2:=lapply(.SD,c),.SDcols=A1:B3,by=id] # x2 equals A1
dt[,x2:=sapply(.SD,c),.SDcols=A1:B3,by=id] # x2 equals A1
Any suggestion?
Thanks in advance
=====================================================================
edit: thanks Jaap,
dt[, x2 := lapply(strsplit(x1, ","), as.integer)] # it works
Still, I wonder any beautiful solution?
=====================================================================
edit2:
new solutions, base function is much more useful than I thought.
dt[,ABC0:=apply(rbind(.SD), 1, list),.SDcols=A1:B3,by=id]
dt[,ABC1:=apply(cbind(.SD), 1, list),.SDcols=A1:B3,by=id]
or more simple
dt[,ABC2:=lapply(.SD,rbind),.SDcols=A1:B3]

Automate regression by rows

I have a data.frame
set.seed(100)
exp <- data.frame(exp = c(rep(LETTERS[1:2], each = 10)), re = c(rep(seq(1, 10, 1), 2)), age1 = seq(10, 29, 1), age2 = seq(30, 49, 1),
h = c(runif(20, 10, 40)), h2 = c(40 + runif(20, 4, 9)))
I'd like to make a lm for each row in a data set (h and h2 ~ age1 and age2)
I do it by loop
exp$modelh <- 0
for (i in 1:length(exp$exp)){
age = c(exp$age1[i], exp$age2[i])
h = c(exp$h[i], exp$h2[i])
model = lm(age ~ h)
exp$modelh[i] = coef(model)[1] + 100 * coef(model)[2]
}
and it works well but takes some time with very large files. Will be grateful for the faster solution f.ex. dplyr
Using dplyr, we can try with rowwise() and do. Inside the do, we concatenate (c) the 'age1', 'age2' to create 'age', likewise, we can create 'h', apply lm, extract the coef to create the column 'modelh'.
library(dplyr)
exp %>%
rowwise() %>%
do({
age <- c(.$age1, .$age2)
h <- c(.$h, .$h2)
model <- lm(age ~ h)
data.frame(., modelh = coef(model)[1] + 100*coef(model)[2])
} )
gives the output
# exp re age1 age2 h h2 modelh
#1 A 1 10 30 19.23298 46.67906 68.85506
#2 A 2 11 31 17.73018 47.55402 66.17050
#3 A 3 12 32 26.56967 46.69174 84.98486
#4 A 4 13 33 11.69149 47.74486 61.98766
#5 A 5 14 34 24.05648 46.10051 82.90167
#6 A 6 15 35 24.51312 44.85710 89.21053
#7 A 7 16 36 34.37208 47.85151 113.37492
#8 A 8 17 37 21.10962 48.40977 74.79483
#9 A 9 18 38 26.39676 46.74548 90.34187
#10 A 10 19 39 15.10786 45.38862 75.07002
#11 B 1 20 40 28.74989 46.44153 100.54666
#12 B 2 21 41 36.46497 48.64253 125.34773
#13 B 3 22 42 18.41062 45.74346 81.70062
#14 B 4 23 43 21.95464 48.77079 81.20773
#15 B 5 24 44 32.87653 47.47637 115.95097
#16 B 6 25 45 30.07065 48.44727 101.10688
#17 B 7 26 46 16.13836 44.90204 84.31080
#18 B 8 27 47 20.72575 47.14695 87.00805
#19 B 9 28 48 20.78425 48.94782 84.25406
#20 B 10 29 49 30.70872 44.65144 128.39415
We could do this with the devel version of data.table i.e. v1.9.5. Instructions to install the devel version are here.
We convert the 'data.frame' to 'data.table' (setDT), create a column 'rn' with the option keep.rownames=TRUE. We melt the dataset by specifying the patterns in the measure to convert from 'wide' to 'long' format. Grouped by 'rn', we do the lm and get the coef. This can be assigned as a new column in the original dataset ('exp') while removing the unwanted 'rn' column by assigning (:=) it to NULL.
library(data.table)#v1.9.5+
modelh <- melt(setDT(exp, keep.rownames=TRUE), measure=patterns('^age', '^h'),
value.name=c('age', 'h'))[, {model <- lm(age ~h)
coef(model)[1] + 100 * coef(model)[2]},rn]$V1
exp[, modelh:= modelh][, rn := NULL]
exp
# exp re age1 age2 h h2 modelh
# 1: A 1 10 30 19.23298 46.67906 68.85506
# 2: A 2 11 31 17.73018 47.55402 66.17050
# 3: A 3 12 32 26.56967 46.69174 84.98486
# 4: A 4 13 33 11.69149 47.74486 61.98766
# 5: A 5 14 34 24.05648 46.10051 82.90167
# 6: A 6 15 35 24.51312 44.85710 89.21053
# 7: A 7 16 36 34.37208 47.85151 113.37492
# 8: A 8 17 37 21.10962 48.40977 74.79483
# 9: A 9 18 38 26.39676 46.74548 90.34187
#10: A 10 19 39 15.10786 45.38862 75.07002
#11: B 1 20 40 28.74989 46.44153 100.54666
#12: B 2 21 41 36.46497 48.64253 125.34773
#13: B 3 22 42 18.41062 45.74346 81.70062
#14: B 4 23 43 21.95464 48.77079 81.20773
#15: B 5 24 44 32.87653 47.47637 115.95097
#16: B 6 25 45 30.07065 48.44727 101.10688
#17: B 7 26 46 16.13836 44.90204 84.31080
#18: B 8 27 47 20.72575 47.14695 87.00805
#19: B 9 28 48 20.78425 48.94782 84.25406
#20: B 10 29 49 30.70872 44.65144 128.39415
Great (double) answer from #akrun.
Just a suggestion for your future analysis as you mentioned "it's an example of a bigger problem". Obviously, if you are really interested in building models rowwise then you'll create more and more columns as your age and h observations increase. If you get N observations you'll have to use 2xN columns for those 2 variables only.
I'd suggest to use a long data format in order to increase your rows instead of your columns.
Something like:
exp[1,] # how your first row (model building info) looks like
# exp re age1 age2 h h2
# 1 A 1 10 30 19.23298 46.67906
reshape(exp[1,], # how your model building info is transformed
varying = list(c("age1","age2"),
c("h","h2")),
v.names = c("age_value","h_value"),
direction = "long")
# exp re time age_value h_value id
# 1.1 A 1 1 10 19.23298 1
# 1.2 A 1 2 30 46.67906 1
Apologies if the "bigger problem" refers to something else and this answer is irrelevant.
With base R, the function sprintf can help us create formulas. And lapply carries out the calculation.
strings <- sprintf("c(%f,%f) ~ c(%f,%f)", exp$age1, exp$age2, exp$h, exp$h2)
lst <- lapply(strings, function(x) {model <- lm(as.formula(x));coef(model)[1] + 100 * coef(model)[2]})
exp$modelh <- unlist(lst)
exp
# exp re age1 age2 h h2 modelh
# 1 A 1 10 30 19.23298 46.67906 68.85506
# 2 A 2 11 31 17.73018 47.55402 66.17050
# 3 A 3 12 32 26.56967 46.69174 84.98486
# 4 A 4 13 33 11.69149 47.74486 61.98766
# 5 A 5 14 34 24.05648 46.10051 82.90167
# 6 A 6 15 35 24.51312 44.85710 89.21053
# 7 A 7 16 36 34.37208 47.85151 113.37493
# 8 A 8 17 37 21.10962 48.40977 74.79483
# 9 A 9 18 38 26.39676 46.74548 90.34187
# 10 A 10 19 39 15.10786 45.38862 75.07002
# 11 B 1 20 40 28.74989 46.44153 100.54666
# 12 B 2 21 41 36.46497 48.64253 125.34773
# 13 B 3 22 42 18.41062 45.74346 81.70062
# 14 B 4 23 43 21.95464 48.77079 81.20773
# 15 B 5 24 44 32.87653 47.47637 115.95097
# 16 B 6 25 45 30.07065 48.44727 101.10688
# 17 B 7 26 46 16.13836 44.90204 84.31080
# 18 B 8 27 47 20.72575 47.14695 87.00805
# 19 B 9 28 48 20.78425 48.94782 84.25406
# 20 B 10 29 49 30.70872 44.65144 128.39416
In the lapply function the expression as.formula(x) is what converts the formulas created in the first line into a format usable by the lm function.
Benchmark
library(dplyr)
library(microbenchmark)
set.seed(100)
big.exp <- data.frame(age1=sample(30, 1e4, T),
age2=sample(30:50, 1e4, T),
h=runif(1e4, 10, 40),
h2= 40 + runif(1e4,4,9))
microbenchmark(
plafort = {strings <- sprintf("c(%f,%f) ~ c(%f,%f)", big.exp$age1, big.exp$age2, big.exp$h, big.exp$h2)
lst <- lapply(strings, function(x) {model <- lm(as.formula(x));coef(model)[1] + 100 * coef(model)[2]})
big.exp$modelh <- unlist(lst)},
akdplyr = {big.exp %>%
rowwise() %>%
do({
age <- c(.$age1, .$age2)
h <- c(.$h, .$h2)
model <- lm(age ~ h)
data.frame(., modelh = coef(model)[1] + 100*coef(model)[2])
} )}
,times=5)
t: seconds
expr min lq mean median uq max neval cld
plafort 13.00605 13.41113 13.92165 13.56927 14.53814 15.08366 5 a
akdplyr 26.95064 27.64240 29.40892 27.86258 31.02955 33.55940 5 b
(Note: I downloaded the newest 1.9.5 devel version of data.table today, but continued to receive errors when trying to test it.
The results also differ fractionally (1.93 x 10^-8). Rounding likely accounts for the difference.)
all.equal(pl, ak)
[1] "Attributes: < Component “class”: Lengths (1, 3) differ (string compare on first 1) >"
[2] "Attributes: < Component “class”: 1 string mismatch >"
[3] "Component “modelh”: Mean relative difference: 1.933893e-08"
Conclusion
The lapply approach seems to perform well compared to dplyr with respect to speed, but it's 5 digit rounding may be an issue. Improvements may be possible. Perhaps using apply after converting to matrix to increase speed and efficiency.

Combining factor levels in R 3.2.1

In previous versions of R I could combine factor levels that didn't have a "significant" threshold of volume using the following little function:
whittle = function(data, cutoff_val){
#convert to a data frame
tab = as.data.frame.table(table(data))
#returns vector of indices where value is below cutoff_val
idx = which(tab$Freq < cutoff_val)
levels(data)[idx] = "Other"
return(data)
}
This takes in a factor vector, looks for levels that don't appear "often enough" and combines all of those levels into one "Other" factor level. An example of this is as follows:
> sort(table(data$State))
05 27 35 40 54 84 9 AP AU BE BI DI G GP GU GZ HN HR JA JM KE KU L LD LI MH NA
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
OU P PL RM SR TB TP TW U VD VI VS WS X ZH 47 BL BS DL M MB NB RP TU 11 DU KA
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 3 3 3
BW ND NS WY AK SD 13 QC 01 BC MT AB HE ID J NO LN NM ON NE VT UT IA MS AO AR ME
4 4 4 4 5 5 6 6 7 7 7 8 8 8 9 10 11 17 23 26 26 30 31 31 38 40 44
OR KS HI NV WI OK KY IN WV AL CO WA MN NH MO SC LA TN AZ IL NC MI GA OH ** CT DE
45 47 48 57 57 64 106 108 112 113 120 125 131 131 135 138 198 200 233 492 511 579 645 646 840 873 1432
RI DC TX MA FL VA MD CA NJ PA NY
1782 2513 6992 7027 10527 11016 11836 12221 15485 16359 34045
Now when I use whittle it returns me the following message:
> delete = whittle(data$State, 1000)
Warning message:
In `levels<-`(`*tmp*`, value = c("Other", "Other", "Other", "Other", :
duplicated levels in factors are deprecated
How can I modify my function so that it has the same effect but doesn't use these "deprecated" factor levels? Converting to a character, tabling, and then converting to the character "Other"?
I've always found it easiest (less typing and less headache) to convert to character and back for these sorts of operations. Keeping with your as.data.frame.table and using replace to do the replacement of the low-frequency levels:
whittle <- function(data, cutoff_val) {
tab = as.data.frame.table(table(data))
factor(replace(as.character(data), data %in% tab$data[tab$Freq < cutoff_val], "Other"))
}
Testing on some sample data:
state <- factor(c("MD", "MD", "MD", "VA", "TX"))
whittle(state, 2)
# [1] MD MD MD Other Other
# Levels: MD Other
I think this verison should work. The levels<- function allows you to collapse by assigning a list (see ?levels).
whittle <- function(data, cutoff_val){
tab <- table(data)
shouldmerge <- tab < cutoff_val
tokeep <- names(tab)[!shouldmerge]
tomerge <- names(tab)[shouldmerge]
nv <- c(as.list(setNames(tokeep,tokeep)), list("Other"=tomerge))
levels(data)<-nv
return(data)
}
And we test it with
set.seed(15)
x<-factor(c(sample(letters[1:10], 100, replace=T), sample(letters[11:13], 10, replace=T)))
table(x)
# x
# a b c d e f g h i j k l m
# 5 11 8 8 7 5 13 14 14 15 2 3 5
y <- whittle(x, 9)
table(y)
# y
# b g h i j Other
# 11 13 14 14 15 43
It's worth adding to this answer that the new forcats package contains the fct_lump() function which is dedicated to this.
Using #MrFlick's data:
x <- factor(c(sample(letters[1:10], 100, replace=T),
sample(letters[11:13], 10, replace=T)))
library(forcats)
library(magrittr) ## for %>% ; could also load dplyr
fct_lump(x, n=5) %>% table
# b g h i j Other
#11 13 14 14 15 43
The n argument specifies the number of most common values to preserve.
Here's another way of doing it by replacing all the items below the threshold with the first and then renaming that level to Other.
whittle <- function(x, thresh) {
belowThresh <- names(which(table(x) < thresh))
x[x %in% belowThresh] <- belowThresh[1]
levels(x)[levels(x) == belowThresh[1]] <- "Other"
factor(x)
}

plot plate layout heatmap in r

I am trying to plot a plate layout heatmap in R. The plate layout is simply 8 (row) x 12 (column) circles (wells). Rows are labeled by alphabets and columns by numbers. Each well need to be filled with some color intensity depends upon a qualitative or quantitative variable. The plate layout look like this:
Here is small dataset:
set.seed (123)
platelay <- data.frame (rown = rep (letters[1:8], 12), coln = rep (1:12, each = 8),
colorvar = rnorm (96, 0.3, 0.2))
rown coln colorvar
1 a 1 0.187904871
2 b 1 0.253964502
3 c 1 0.611741663
4 d 1 0.314101678
5 e 1 0.325857547
6 f 1 0.643012997
7 g 1 0.392183241
8 h 1 0.046987753
9 a 2 0.162629430
10 b 2 0.210867606
11 c 2 0.544816359
12 d 2 0.371962765
13 e 2 0.380154290
14 f 2 0.322136543
15 g 2 0.188831773
16 h 2 0.657382627
17 a 3 0.399570096
18 b 3 -0.093323431
19 c 3 0.440271180
20 d 3 0.205441718
21 e 3 0.086435259
22 f 3 0.256405017
23 g 3 0.094799110
24 h 3 0.154221754
25 a 4 0.174992146
26 b 4 -0.037338662
27 c 4 0.467557409
28 d 4 0.330674624
29 e 4 0.072372613
30 f 4 0.550762984
31 g 4 0.385292844
32 h 4 0.240985703
33 a 5 0.479025132
34 b 5 0.475626698
35 c 5 0.464316216
36 d 5 0.437728051
37 e 5 0.410783531
38 f 5 0.287617658
39 g 5 0.238807467
40 h 5 0.223905800
41 a 6 0.161058604
42 b 6 0.258416544
43 c 6 0.046920730
44 d 6 0.733791193
45 e 6 0.541592400
46 f 6 0.075378283
47 g 6 0.219423033
48 h 6 0.206668929
49 a 7 0.455993024
50 b 7 0.283326187
51 c 7 0.350663703
52 d 7 0.294290649
53 e 7 0.291425909
54 f 7 0.573720457
55 g 7 0.254845803
56 h 7 0.603294121
57 a 8 -0.009750561
58 b 8 0.416922750
59 c 8 0.324770849
60 d 8 0.343188314
61 e 8 0.375927897
62 f 8 0.199535309
63 g 8 0.233358523
64 h 8 0.096284923
65 a 9 0.085641755
66 b 9 0.360705728
67 c 9 0.389641956
68 d 9 0.310600845
69 e 9 0.484453494
70 f 9 0.710016937
71 g 9 0.201793767
72 h 9 -0.161833775
73 a 10 0.501147705
74 b 10 0.158159847
75 c 10 0.162398277
76 d 10 0.505114274
77 e 10 0.243045399
78 f 10 0.055856458
79 g 10 0.336260696
80 h 10 0.272221728
81 a 11 0.301152837
82 b 11 0.377056080
83 c 11 0.225867994
84 d 11 0.428875310
85 e 11 0.255902688
86 f 11 0.366356393
87 g 11 0.519367803
88 h 11 0.387036298
89 a 12 0.234813683
90 b 12 0.529761524
91 c 12 0.498700771
92 d 12 0.409679392
93 e 12 0.347746347
94 f 12 0.174418785
95 g 12 0.572130490
96 h 12 0.179948083
Is there is package that can readily do it ? Is it possible write a function in base or ggplot2 or other package that can achieve this target.
Changing the colour of points of sufficient size, with ggplot2. Note I've implemeted #TylerRinkler's suggestion, but within the call to ggplot. I've also removed the axis labels
ggplot(platelay, aes(y = factor(rown, rev(levels(rown))),x = factor(coln))) +
geom_point(aes(colour = colorvar), size =18) +theme_bw() +
labs(x=NULL, y = NULL)
And a base graphics approach, which will let you have the x axis above the plot
# plot with grey colour dictated by rank, no axes or labels
with(platelay, plot( x=as.numeric(coln), y= rev(as.numeric(rown)), pch= 19, cex = 2,
col = grey(rank(platelay[['colorvar']] ) / nrow(platelay)), axes = F, xlab= '', ylab = ''))
# add circular outline
with(platelay, points( x=as.numeric(coln), y= rev(as.numeric(rown)), pch= 21, cex = 2))
# add the axes
axis(3, at =1:12, labels = 1:12)
axis(2, at = 1:8, labels = LETTERS[8:1])
# the background grid
grid()
# and a box around the outside
box()
And for giggles and Christmas cheer, here is a version using base R plotting functions.
Though there is very possibly a better solution.
dev.new(width=6,height=4)
rown <- unique(platelay$rown)
coln <- unique(platelay$coln)
plot(NA,ylim=c(0.5,length(rown)+0.5),xlim=c(0.5,length(coln)+0.5),ann=FALSE,axes=FALSE)
box()
axis(2,at=seq_along(rown),labels=rev(rown),las=2)
axis(3,at=seq_along(coln),labels=coln)
colgrp <- findInterval(platelay$colorvar,seq(min(platelay$colorvar),max(platelay$colorvar),length.out=10))
colfunc <- colorRampPalette(c("green", "blue"))
collist <- colfunc(length(unique(colgrp)))
symbols(platelay$coln,
factor(platelay$rown, rev(levels(platelay$rown))),
circles=rep(0.2,nrow(platelay)),
add=TRUE,
inches=FALSE,
bg=collist[colgrp])
And the resulting image:
here a solution using ggplot2 solution of #mnel and grid solution
here the code of given solution
d <- ggplot(platelay, aes(y=rown,x=factor(coln))) +
geom_point(aes(colour = colorvar), size =18) + theme_bw()
I use the data generated by ggplot
data <- ggplot_build(d)$data[[1]]
x <- data$x
y <- data$y
grid.newpage()
pushViewport(plotViewport(c(4, 4, 2, 2)),
dataViewport(x, y))
grid hase an ellipse geom
grid.ellipse(x, y,size=20, ar = 2,angle=0,gp =gpar(fill=data$colour))
grid.xaxis(at=c(labels=1:12,ticks=NA),gp=gpar(cex=2))
grid.yaxis(at = 1:8,label=rev(LETTERS[1:8]),gp=gpar(cex=2))
grid.roundrect(gp=gpar(fill=NA))
I add grid :
gpgrid <- gpar(col='grey',lty=2,col='white')
grid.segments(unit(1:12, "native") ,unit(0, "npc"), unit(1:12, "native"),unit(1, "npc"),gp=gpgrid)
grid.segments(unit(0, "npc"), unit(1:8, "native"), unit(1, "npc"),unit(1:8, "native"),gp=gpgrid)
upViewport()
This answer is an add on for #thelatemail answer which explains the platemap for (8,12) = 96 format.
To construct (32,48) = 1536 format, single digits of A-Z is insufficent. Hence one needs to expand letters such as AA, AB, AC, AD ... ZZ and it can be expanded to three or more digits by concatenating LETTERS to the levels variable as below.
levels = c(LETTERS, c(t(outer(LETTERS, LETTERS, paste, sep = "")))))
#thelatemail answer can be improved for letters in double digits for 1536 plate format as below
rown = rep (c(LETTERS, c(t(outer(LETTERS[1], LETTERS[1:6], paste, sep = "")))),
symbols(platelay$coln,
factor(platelay$rown,
levels = rev(c(LETTERS, c(t(outer(LETTERS[1], LETTERS[1:6], paste, sep = "")))))),
circles=rep(0.45,nrow(platelay)),
add=TRUE,
inches=FALSE,
bg=collist[colgrp])
The levels variable inside symbols function should have characters with alphabetically sorted single, then double, then triple ... and so on digits.
For example, if you have below incorrect order of levels inside the symbols function, then it will plot with incorrect color representation.
Incorrect order:
A, AA, AB, AC, AD, AE, AF, B, C,D, ...Z
Correct order:
A, B, C, D, E, .....Z, AA, AB, AC, AD, AE, AF

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