I have a table in R that I am using to make a barplot:
86 17 482 424 C
87 18 600 426 T
88 11 279 427 Q
89 X 399 436 B
I can make the plot with barplot(table$V3) but how do I use the values in V4 as the names for each V3 entry?
just use
barplot(DF$V3, names.arg=DF$V4)
where DF is your data.frame (a table is something else in R. If you actually mean table, please indicate as such)
Related
I have a data set of counts from standard solutions passed through an instrument that analyses chemical concentrations (an ICPMS for those familiar). The data is over a range of different standards and for each standard I have four repeat measurements that I want to calculate the mean and variance of.
I'm importing the data from an excel spreadsheet and then, following some housekeeping such as getting dates and times in the right format, I split the the dataset up into a list identified by the name of the standard solution using Count11.sp<-split(Count11.raw, Count11.raw$Type). Count11.raw$Type then becomes the list element name and I have the four count results for each chemical element in that list element.
So far so good.
I find I can yield an average (mean, median etc) easily enough by identifying the list element specifically i.e. mean(Count11.sp$'Ca40') , or sapply(Count11$'Ca40', median), but what I'm not able to do is automate that in a loop so that I can calculate the means for each standard and drop that into a numerical matrix for further manipulation. I can extract the list element names with names() and I can even use a loop to make a vector of all the names and reference the specific list element using these in a for loop.
For instance Count11.sp[names(Count11.sp[i])]will extract the full list element no problem:
$`Post Ca45t`
Type Run Date 7Li 9Be 24Mg 43Ca 52Cr 55Mn 59Co 60Ni
77 Post Ca45t 1 2011-02-08 00:13:08 114 26101 4191 453525 2632 520 714 2270
78 Post Ca45t 2 2011-02-08 00:13:24 114 26045 4179 454299 2822 524 704 2444
79 Post Ca45t 3 2011-02-08 00:13:41 96 26372 3961 456293 2898 520 762 2244
80 Post Ca45t 4 2011-02-08 00:13:58 112 26244 3799 454702 2630 510 792 2356
65Cu 66Zn 85Rb 86Sr 111Cd 115In 118Sn 137Ba 140Ce 141Pr 157Gd 185Re 208Pb
77 244 1036 56 3081 44 520625 78 166 724 10 0 388998 613
78 250 982 70 3103 46 526154 76 174 744 16 4 396496 644
79 246 1014 36 3183 56 524195 60 198 744 2 0 396024 612
80 270 932 60 3137 44 523366 70 180 824 2 4 390436 632
238U
77 24
78 20
79 14
80 6
but sapply(Count11.sp[names(count11.sp[i])produces an error message: Error in median.default(X[[i]], ...) : need numeric data
while sapply(Input$Post Ca45t, median) <'Post Ca45t' being name Count11.sp[i] i=4> does exactly what I want and produces the median value (I can clean that vector up later for medians that don't make sense) e.g.
Type Run Date 7Li 9Be 24Mg
NA 2.5 1297109612.5 113.0 26172.5 4070.0
43Ca 52Cr 55Mn 59Co 60Ni 65Cu
454500.5 2727.0 520.0 738.0 2313.0 248.0
66Zn 85Rb 86Sr 111Cd 115In 118Sn
998.0 58.0 3120.0 45.0 523780.5 73.0
137Ba 140Ce 141Pr 157Gd 185Re 208Pb
177.0 744.0 6.0 2.0 393230.0 622.5
238U
17.0
Can anyone give me any insight into how I can automate (i.e. loop through) these names to produce one median vector per list element? I'm sure there's just some simple disconnect in my logic here that may be easily solved.
Update: I've solved the problem. The way to do so is to use tapply on the original dataset with out the need to split it. tapply allows functions to be applied to data based on a user defined grouping criteria. In my case I could group according to the Count11.raw$Type and then take the mean of the data subset. tapply(Count11.raw$Type, Count11.raw[,3:ncol(Count11.raw)], mean), job done.
I have a data set where I have the Levels and Trends for say 50 cities for 3 scenarios. Below is the sample data -
City <- paste0("City",1:50)
L1 <- sample(100:500,50,replace = T)
L2 <- sample(100:500,50,replace = T)
L3 <- sample(100:500,50,replace = T)
T1 <- runif(50,0,3)
T2 <- runif(50,0,3)
T3 <- runif(50,0,3)
df <- data.frame(City,L1,L2,L3,T1,T2,T3)
Now, across the 3 scenarios I find the minimum Level and Minimum Trend using the below code -
df$L_min <- apply(df[,2:4],1,min)
df$T_min <- apply(df[,5:7],1,min)
Now I want to check if these minimum values are significantly different between the levels and trends respectively. So check L_min with columns 2-4 and T_min with columns 5-7. This needs to be done for each city (row) and if significant then return which column it is significantly different with.
It would help if some one could guide how this can be done.
Thank you!!
I'll put my idea here, nevertheless I'm looking forward for ideas for others.
> head(df)
City L1 L2 L3 T1 T2 T3 L_min T_min
1 City1 251 176 263 1.162313 0.07196579 2.0925715 176 0.07196579
2 City2 385 406 264 0.353124 0.66089524 2.5613980 264 0.35312402
3 City3 437 333 426 2.625795 1.43547766 1.7667891 333 1.43547766
4 City4 431 405 493 2.042905 0.93041254 1.3872058 405 0.93041254
5 City5 101 429 100 1.731004 2.89794314 0.3535423 100 0.35354230
6 City6 374 394 465 1.854794 0.57909775 2.7485841 374 0.57909775
> df$FC <- rowMeans(df[,2:4])/df[,8]
> df <- df[order(-df$FC), ]
> head(df)
City L1 L2 L3 T1 T2 T3 L_min T_min FC
18 City18 461 425 117 2.7786757 2.6577894 0.75974121 117 0.75974121 2.857550
38 City38 370 117 445 0.1103141 2.6890014 2.26174542 117 0.11031411 2.655271
44 City44 101 473 222 1.2754675 0.8667007 0.04057544 101 0.04057544 2.627063
10 City10 459 361 132 0.1529519 2.4678493 2.23373484 132 0.15295194 2.404040
16 City16 232 393 110 0.8628494 1.3995549 1.01689217 110 0.86284938 2.227273
15 City15 499 475 182 0.3679611 0.2519497 2.82647041 182 0.25194969 2.117216
Now you have the most different rows based on columns 2:4 at the top. Columns 5:7 in analogous way.
And some tips for stastical tests:
Always use t.test(parametrical, based on mean) instead of wilcoxon(u-mann whitney - non-parametrical, based on median), it has more power; HOWEVER:
-Data sets should be big ex. hipotesis: Montreal has taller citizens than Quebec; t.test will work fine when you take a 100 people from each city, so we have height measurment of 200 people 100 vs 100.
-Distribution should be close to normal distribution in all samples; or both samples should have similar distribution far from normal - it may be binominal. Anyway we can't use this test when one sample has normal distribution, and second hasn't.
-Size of both samples should be eqal, so 100 vs 100 is ok, but 87 vs 234 not exactly, p-value will be below 0.05, however it may be misrepresented.
If your data doesn't meet above conditions, I prefer non-parametrical test, less power but more resistant.
Sorry for the confusing title, but i wasn't sure how to title what i am trying to do. My objective is to create a dataset of 1000 obs each would be the length of the run. I have created a phase1 dataset, from which a set of control limits are produced. What i am trying to do now is create a phase2 dataset most likely using rnorm. what im trying to do is create a repeat loop that will continuously create values in the phase2 dataset until one of those values is outside of the control limits produced from the phase1 dataset. for example if i had 3.0 and -3.0 as control limits the phase2 dataset would create a bunch of observations until obs 398 when the value here happens to be 3.45, thus stopping the creation of data. my objective is then to record the number 398. Furthermore, I am then trying to loop the code back to the phase1 dataset/ control limits portion and create a new set of control limits and then run another phase2, until i have 1000 run lengths recorded. the code i have for the phase1/ control limits works fine and looks like this:
nphase1=50
nphase2=1000
varcount=1
meanshift= 0
sigmashift= 1
##### phase1 dataset/ control limits #####
phase1 <- matrix(rnorm(nphase1*varcount, 0, 1), nrow = nphase1, ncol=varcount)
mean_var <- apply(phase1, 2, mean)
std_var <- apply(phase1, 2, sd)
df_var <- data.frame(mean_var, std_var)
Upper_SPC_Limit_Method1 <- with(df_var, mean_var + 3 * std_var)
Lower_SPC_Limit_Method1 <- with(df_var, mean_var - 3 * std_var)
df_control_limits<- data.frame(Upper_SPC_Limit_Method1, Lower_SPC_Limit_Method1)
I have previously created this code in SAS and it looks like this. might be a better reference for what i am trying to achieve then me trying to explain it.
%macro phase2_dataset (n=,varcount=, meanshift=, sigmashift=, nphase1=,simID=,);
%do z=1 %to &n;
%phase1_dataset (n=&nphase1, varcount=&varcount);
data phase2; set control_limits n=lastobs;
call streaminit(0);
do until (phase2_var1<Lower_SPC_limit_method1_var1 or
phase2_var1>Upper_SPC_limit_method1_var1);
phase2_var1 = rand("normal", &meanshift, &sigmashift);
output;
end;
run;
ods exclude all;
proc means data=phase2;
var phase2_var1;
ods output summary=x;
run;
ods select all;
data run_length; set x;
keep Phase2_var1_n;
run;
proc append base= QA.Phase2_dataset&simID data=Run_length force; run;
%end;
%mend;
Also been doing research about using a while loop in replace of the repeat loop.
Im new to R so Any ideas you are able to throw my way are greatly appreciated. Thanks!
Using a while loop indeed seems to be the way to go. Here's what I think you're looking for:
set.seed(10) #Making results reproducible
replicate(100, { #100 is easier to display here
phase1 <- matrix(rnorm(nphase1*varcount, 0, 1), nrow = nphase1, ncol=varcount)
mean_var <- colMeans(phase1) #Slightly better than apply
std_var <- apply(phase1, 2, sd)
df_var <- data.frame(mean_var, std_var)
Upper_SPC_Limit_Method1 <- with(df_var, mean_var + 3 * std_var)
Lower_SPC_Limit_Method1 <- with(df_var, mean_var - 3 * std_var)
df_control_limits<- data.frame(Upper_SPC_Limit_Method1, Lower_SPC_Limit_Method1)
#Phase 2
x <- 0
count <- 0
while(x > Lower_SPC_Limit_Method1 && x < Upper_SPC_Limit_Method1) {
x <- rnorm(1)
count <- count + 1
}
count
})
The result is:
[1] 225 91 97 118 304 275 550 58 115 6 218 63 176 100 308 844 90 2758
[19] 161 311 1462 717 2446 74 175 91 331 210 118 1517 420 32 39 201 350 89
[37] 64 385 212 4 72 730 151 7 1159 65 36 333 97 306 531 1502 26 18
[55] 67 329 75 532 64 427 39 352 283 483 19 9 2 1018 137 160 223 98
[73] 15 182 98 41 25 1136 405 474 1025 1331 159 70 84 129 233 2 41 66
[91] 1 23 8 325 10 455 363 351 108 3
If performance becomes a problem, perhaps it would be interesting to explore some improvements, like creating more numbers with rnorm() at a time and then counting how many are necessary to exceed the limits and repeat if necessary.
I am a beginner with R . My data looks like this:
id count date
1 210 2009.01
2 400 2009.02
3 463 2009.03
4 465 2009.04
5 509 2009.05
6 861 2009.06
7 872 2009.07
8 886 2009.08
9 725 2009.09
10 687 2009.10
11 762 2009.11
12 748 2009.12
13 678 2010.01
14 699 2010.02
15 860 2010.03
16 708 2010.04
17 709 2010.05
18 770 2010.06
19 784 2010.07
20 694 2010.08
21 669 2010.09
22 689 2010.10
23 568 2010.11
24 584 2010.12
25 592 2011.01
26 548 2011.02
27 683 2011.03
28 675 2011.04
29 824 2011.05
30 637 2011.06
31 700 2011.07
32 724 2011.08
33 629 2011.09
34 446 2011.10
35 458 2011.11
36 421 2011.12
37 459 2012.01
38 256 2012.02
39 341 2012.03
40 284 2012.04
41 321 2012.05
42 404 2012.06
43 418 2012.07
44 520 2012.08
45 546 2012.09
46 548 2012.10
47 781 2012.11
48 704 2012.12
49 765 2013.01
50 571 2013.02
51 371 2013.03
I would like to make a bar graph like graph that shows how much what is the count for each date (dates in format of Month-Y, Jan-2009 for instance). I have two issues:
1- I cannot find a good format for a bar-char like graph like that
2- I want all of my data-points to be present in X axis(date), while R aggregates it to each year only (so I inly have four data-points there). Below is the current command that I am using:
plot(df$date,df$domain_count,col="red",type="h")
and my current plot is like this:
Ok, I see some issues in your original data. May I suggest the following:
Add the days in your date column
df$date=paste(df$date,'.01',sep='')
Convert the date column to be of date type:
df$date=as.Date(df$date,format='%Y.%m.%d')
Plot the data again:
plot(df$date,df$domain_count,col="red",type="h")
Also, may I add one more suggestion, have you used ggplot for ploting chart? I think you will find it much easier and resulting in better looking charts. Your example could be visualized like this:
library(ggplot2) #if you don't have the package, run install.packages('ggplot2')
ggplot(df,aes(date, count))+geom_bar(stat='identity')+labs(x="Date", y="Count")
First, you should transform your date column in a real date:
library(plyr) # for mutate
d <- mutate(d, month = as.numeric(gsub("[0-9]*\\.([0-9]*)", "\\1", as.character(date))),
year = as.numeric(gsub("([0-9]*)\\.[0-9]*", "\\1", as.character(date))),
Date = ISOdate(year, month, 1))
Then, you could use ggplot to create a decent barchart:
library(ggplot2)
ggplot(d, aes(x = Date, y = count)) + geom_bar(fill = "red", stat = "identity")
You can also use basic R to create a barchart, which is however less nice:
dd <- setNames(d$count, format(d$Date, "%m-%Y"))
barplot(dd)
The former plot shows you the "holes" in your data, i.e. month where there is no count, while for the latter it is even wuite difficult to see which bar corresponds to which month (this could however be tweaked I assume).
Hope that helps.
Let's say I'd like to calculate the magnitude of the range over a few columns, on a row-by-row basis.
set.seed(1)
dat <- data.frame(x=sample(1:1000,1000),
y=sample(1:1000,1000),
z=sample(1:1000,1000))
Using data.frame(), I would do something like this:
dat$diff_range <- apply(dat,1,function(x) diff(range(x)))
To put it more simply, I'm looking for this operation, over each row:
diff(range(dat[1,]) # for i 1:nrow(dat)
If I were doing this for the entire table, it would be something like:
setDT(dat)[,diff_range := apply(dat,1,function(x) diff(range(x)))]
But how would I do it for only named (or numbered) rows?
pmax and pmin find the min and max across columns in a vectorized way, which is much better than splitting and working with each row separately. It's also pretty concise:
dat[, r := do.call(pmax,.SD) - do.call(pmin,.SD)]
x y z r
1: 266 531 872 606
2: 372 685 967 595
3: 572 383 866 483
4: 906 953 437 516
5: 201 118 192 83
---
996: 768 945 292 653
997: 61 231 965 904
998: 771 145 18 753
999: 841 148 839 693
1000: 857 252 218 639
How about this:
D[,list(I=.I,x,y,z)][,diff(range(x,y,z)),by=I][c(1:4,15:18)]
# I V1
#1: 1 971
#2: 2 877
#3: 3 988
#4: 4 241
#5: 15 622
#6: 16 684
#7: 17 971
#8: 18 835
#actually this will be faster
D[c(1:4,15:18),list(I=.I,x,y,z)][,diff(range(x,y,z)),by=I]
use .I to give you an index to call with the by= parameter, then you can run the function on each row. The second call pre-filters by any list of row numbers, or you can add a key and filter on that if your real table looks different.
You can do it by subsetting before/during the function. If you only want every second row for example
dat_Diffs <- apply(dat[seq(2,1000,by=2),],1,function(x) diff(range(x)))
Or for rownames 1:10 (since their names weren't specified they are just numbers counting up)
dat_Diffs <- apply(dat[rownames(dat) %in% 1:10,],1,function(x) diff(range(x)))
But why not just calculate per row then subset later?