aboutsummaryrefslogtreecommitdiff
path: root/R/drfit.R
blob: d8631e6d873ad524fd5bb5e0555ce982e021fe6e (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
drdata <- function(substances, experimentator = "%", db = "cytotox",
    celltype="IPC-81",enzymetype="AChE",
    organism="Vibrio fischeri",endpoint="Luminescence",whereClause="1",
    ok="'ok','no fit'")
{
    library(RODBC) 
    channel <- odbcConnect(db,uid="cytotox",pwd="cytotox",case="tolower")
    slist <- paste(substances,collapse="','")
    if (db == "cytotox") {
        responsetype <- "viability"
        testtype <- "celltype"
        type <- celltype
    } else {
        if (db == "enzymes") {
            responsetype <- "activity"
            testtype <- "enzyme"
            type <- enzymetype
        } else {
            responsetype <- "response"
            testtype <- "organism"
            type <- organism
        }
    }
        
    query <- paste("SELECT conc,",responsetype,",unit,experimentator,substance,",testtype,
        ",ok FROM ", db, " WHERE substance IN ('",
        slist,"') AND experimentator LIKE '",
        experimentator,"' AND ",testtype," LIKE '",
        type,"' AND ",
        whereClause," AND ok in (",
        ok,")",sep="")
    if (db == "ecotox") query <- paste(query," AND type LIKE '",endpoint,"'",sep="")
    data <- sqlQuery(channel,query)
    odbcClose(channel)
    names(data)[[1]] <- "dose"
    names(data)[[2]] <- "response"
    data$dosefactor <- factor(data$dose)
    data$substance <- factor(data$substance,levels=substances)
    return(data)
}
    
linlogitf <- function(x,k,f,mu,b)
{
    k*(1 + f*x) / (1 + ((2*f*(10^mu) + 1) * ((x/(10^mu))^b)))
}

drfit <- function(data, startlogEC50 = NA, chooseone=TRUE,
        probit = TRUE, logit = FALSE, weibull = FALSE,
        linlogit = FALSE, linlogitWrong = NA, allWrong = NA,
        s0 = 0.5, b0 = 2, f0 = 0)
{
    if(!is.null(data$ok)) data <- subset(data,ok!="no fit") # Don't use data where ok 
                                                            # was set to "no fit"
    substances <- levels(data$substance)

    ri <- rix <- 0                        # ri is the index over the result rows
                                          # rix is used later to check if any
                                          # model result was appended
    rsubstance <- array()                 # the substance names in the results
    rn <- vector()                        # number of dose-response curves 
    runit <- vector()                     # vector of units for each result row
    rlhd <- rlld <- vector()              # highest and lowest doses tested
    mtype <- array()                      # the modeltypes
    sigma <- array()                      # the standard deviation of the residuals
    logEC50 <- vector()
    stderrlogEC50 <- vector()
    a <- b <- c <- vector()

    splitted <- split(data,data$substance)
    for (i in substances) {
        tmp <- splitted[[i]]
        fit <- FALSE
        if (length(tmp) != 0) {
            unit <- levels(as.factor(as.vector(tmp$unit)))
            cat("\n",i,": Fitting data...\n",sep="")
        } else {
            unit <- ""
            cat("\n",i,": No data\n",sep="")
        }
        if (length(unit) > 1) {
            cat("More than one unit for substance ",i,", halting\n\n",sep="")
            break
        }
        n <- round(length(tmp$response)/9)
        if (length(tmp$response) == 0) {
            nodata = TRUE
        } else {
            nodata = FALSE
        }
        rix <- ri
        if (!nodata) {
            if (is.na(startlogEC50[i])){
                w <- 1/abs(tmp$response - 0.3)
                startlogEC50[[i]] <- sum(w * log10(tmp$dose))/sum(w)
            }
            highestdose <- max(tmp$dose)
            lowestdose <- min(tmp$dose)
            lhd <- log10(highestdose)
            lld <- log10(lowestdose)
            responseathighestdose <- mean(subset(tmp,dose==highestdose)$response)
            if (responseathighestdose < 0.5) {
                inactive <- FALSE

                if (linlogit && 
                    length(subset(linlogitWrong,linlogitWrong == i))==0 &&
                    length(subset(allWrong,allWrong == i))==0) {
                    m <- try(nls(response ~ linlogitf(dose,1,f,logEC50,b),
                            data=tmp,
                            start=list(f=f0,logEC50=startlogEC50[[i]],b=b0)))
                    if (!inherits(m, "try-error")) {
                        fit <- TRUE
                        ri <- ri + 1
                        s <- summary(m)
                        sigma[[ri]] <- s$sigma
                        rsubstance[[ri]] <- i
                        rn[[ri]] <- n
                        runit[[ri]] <- unit
                        rlld[[ri]] <- log10(lowestdose)
                        rlhd[[ri]] <- log10(highestdose)
                        logEC50[[ri]] <- coef(m)[["logEC50"]]
                        if (logEC50[[ri]] > rlhd[[ri]]) {
                            mtype[[ri]] <- "no fit"
                            logEC50[[ri]] <- NA
                            stderrlogEC50[[ri]] <- NA
                            a[[ri]] <- NA
                            b[[ri]] <- NA
                            c[[ri]] <- NA
                        } else {
                            mtype[[ri]] <- "linlogit"
                            stderrlogEC50[[ri]] <- s$parameters["logEC50","Std. Error"]
                            a[[ri]] <- coef(m)[["logEC50"]]
                            b[[ri]] <- coef(m)[["b"]]
                            c[[ri]] <- coef(m)[["f"]]
                        }
                    }
                }

                if (probit &&
                    length(subset(allWrong,allWrong == i))==0) {
                    m <- try(nls(response ~ pnorm(-log10(dose),-logEC50,scale),
                                data=tmp,
                                start=list(logEC50=startlogEC50[[i]],scale=1)))
                    if (chooseone==FALSE || fit==FALSE) {
                        if (!inherits(m, "try-error")) {
                            fit <- TRUE
                            ri <- ri + 1
                            s <- summary(m)
                            sigma[[ri]] <- s$sigma
                            rsubstance[[ri]] <- i
                            rn[[ri]] <- n
                            runit[[ri]] <- unit
                            rlld[[ri]] <- log10(lowestdose)
                            rlhd[[ri]] <- log10(highestdose)
                            logEC50[[ri]] <- coef(m)[["logEC50"]]
                            c[[ri]] <- NA
                            if (logEC50[[ri]] > rlhd[[ri]]) {
                                mtype[[ri]] <- "no fit"
                                logEC50[[ri]] <- NA
                                stderrlogEC50[[ri]] <- NA
                                a[[ri]] <- NA
                                b[[ri]] <- NA
                            } else {
                                mtype[[ri]] <- "probit"
                                stderrlogEC50[[ri]] <- s$parameters["logEC50","Std. Error"]
                                a[[ri]] <- coef(m)[["logEC50"]]
                                b[[ri]] <- coef(m)[["scale"]]
                            }
                        }
                    }
                }

                if (logit &&
                    length(subset(allWrong,allWrong == i))==0) {
                    m <- try(nls(response ~ plogis(-log10(dose),-logEC50,scale),
                            data=tmp,
                            start=list(logEC50=startlogEC50[[i]],scale=1)))
                    if (chooseone==FALSE || fit==FALSE) {
                        if (!inherits(m, "try-error")) {
                            fit <- TRUE
                            ri <- ri + 1
                            s <- summary(m)
                            sigma[[ri]] <- s$sigma
                            rsubstance[[ri]] <- i
                            rn[[ri]] <- n
                            runit[[ri]] <- unit
                            rlld[[ri]] <- log10(lowestdose)
                            rlhd[[ri]] <- log10(highestdose)
                            logEC50[[ri]] <- a[[ri]] <- coef(m)[["logEC50"]]
                            b[[ri]] <- coef(m)[["scale"]]
                            c[[ri]] <- NA
                            if (logEC50[[ri]] > rlhd[[ri]]) {
                                mtype[[ri]] <- "no fit"
                                logEC50[[ri]] <- NA
                                stderrlogEC50[[ri]] <- NA
                                a[[ri]] <- NA
                                b[[ri]] <- NA
                            } else {
                                mtype[[ri]] <- "logit"
                                stderrlogEC50[[ri]] <- s$parameters["logEC50","Std. Error"]
                            }
                        }
                    }
                }

                if (weibull &&
                    length(subset(allWrong,allWrong == i))==0) {
                    m <- try(nls(response ~ pweibull(-log10(dose)+location,shape),
                            data=tmp,
                            start=list(location=startlogEC50[[i]],shape=s0)))
                    if (chooseone==FALSE || fit==FALSE) {
                        if (!inherits(m, "try-error")) {
                            fit <- TRUE
                            ri <- ri + 1
                            s <- summary(m)
                            sigma[[ri]] <- s$sigma
                            rsubstance[[ri]] <- i
                            rn[[ri]] <- n
                            runit[[ri]] <- unit
                            rlld[[ri]] <- log10(lowestdose)
                            rlhd[[ri]] <- log10(highestdose)
                            a[[ri]] <- coef(m)[["location"]]
                            b[[ri]] <- coef(m)[["shape"]]
                            sqrdev <- function(logdose) {
                                (0.5 - pweibull( - logdose + a[[ri]], b[[ri]]))^2 
                            }
                            logEC50[[ri]] <- nlm(sqrdev,startlogEC50[[i]])$estimate
                            c[[ri]] <- NA
                            if (logEC50[[ri]] > rlhd[[ri]]) {
                                mtype[[ri]] <- "no fit"
                                logEC50[[ri]] <- NA
                                stderrlogEC50[[ri]] <- NA
                                a[[ri]] <- NA
                                b[[ri]] <- NA
                            } else {
                                mtype[[ri]] <- "weibull"
                                stderrlogEC50[[ri]] <- NA
                            }
                        }
                    }
                }


            } else {
                inactive <- TRUE
            }
        }
        if (ri == rix) {          # if no entry was appended for this substance
            ri <- ri + 1
            rsubstance[[ri]] <- i
            rn[[ri]] <- n
            if (nodata) {
                rlld[[ri]] <- rlhd[[i]] <- NA
                mtype[[ri]] <- "no data"
                runit[[ri]] <- NA
            } else {
                rlld[[ri]] <- log10(lowestdose)
                rlhd[[i]] <- log10(highestdose)
                runit[[ri]] <- unit
                if (inactive) {
                    mtype[[ri]] <- "inactive"
                } else {
                    mtype[[ri]] <- "no fit"
                }
            }
            sigma[[ri]] <- NA
            logEC50[[ri]] <- NA
            stderrlogEC50[[ri]] <- NA
            a[[ri]] <- NA
            b[[ri]] <- NA
            c[[ri]] <- NA
        }
    }
    results <- data.frame(rsubstance, rn, rlld, rlhd, mtype, logEC50, stderrlogEC50, runit, sigma, a, b)
    names(results) <- c("Substance","n","lld","lhd","mtype","logEC50","std","unit","sigma","a","b")
    if (linlogit) {
        results$c <- c
    }
    return(results)
}

drplot <- function(drresults, data, dtype = "std", alpha = 0.95,
        path = "./", fileprefix = "drplot", overlay = FALSE,
        postscript = FALSE, png = FALSE, bw = TRUE,
        pointsize = 12,
        colors = 1:8, devoff=T, lpos="topright")
{
    # Check if all data have the same unit
    unitlevels <- levels(as.factor(drresults$unit))
    if (length(unitlevels) == 1) {
        unit <- unitlevels
    } else {
        unit <- "different units"
    }

    # Get the plot limits on the x-axis (log of the dose)
    if(is.data.frame(data)) {
        if (min(data$dose) == 0) {
            cat("At least one of the dose levels is 0 - this is not a valid dose.")
        } else {
            lld <- log10(min(data$dose))
        }
        lhd <- log10(max(data$dose))
        hr <- max(data$response)
        dsubstances <- levels(data$substance)    
    } else {
        lld <- min(drresults[["logEC50"]],na.rm=TRUE) - 2
        lhd <- max(drresults[["logEC50"]],na.rm=TRUE) + 2
        if (length(subset(drresults,mtype=="linlogit")$Substance) != 0) {
            hr <- 1.8 
        } else {
            hr <- 1.0
        }
    }

    # Prepare overlay plot if requested
    if (overlay)
    {
        if (postscript) {
            filename = paste(path,fileprefix,".eps",sep="")
            postscript(file=filename,
                    paper="special",width=7,height=7,horizontal=FALSE, pointsize=pointsize)
            cat("Created File: ",filename,"\n")
        } 
        if (png) {
            filename = paste(path,fileprefix,".png",sep="")
            png(filename=filename,
                width=500, height=500, pointsize=pointsize)
            cat("Created File: ",filename,"\n")
        }
        if (!postscript && !png) {
            get(getOption("device"))(width=7,height=7)
        }
            
        plot(0,type="n",
            xlim=c(lld - 0.5, lhd + 1),
            ylim= c(-0.1, hr + 0.2),
            xlab=paste("Decadic Logarithm of the dose in ", unit),    
            ylab="Normalized response")
    }

    # Plot the data either as raw data or as error bars
    if(is.data.frame(data)) {
        splitted <- split(data,data$substance)
        # n is the index for the dose-response curves
        n <- 0
        if (bw) colors <- rep("black",length(dsubstances))
        # Loop over the substances in the data
        for (i in dsubstances) {
            n <- n + 1
            tmp <- splitted[[i]]
            if (length(tmp$response) != 0) {
                color <- colors[[n]]
                # Prepare the single graphs if an overlay is not requested
                if (!overlay)
                {
                    if (postscript) {
                        filename = paste(path,fileprefix,sub(" ","_",i),".eps",sep="")
                        postscript(file=filename,
                                paper="special",width=7,height=7,horizontal=FALSE,pointsize=pointsize)
                        cat("Created File: ",filename,"\n")
                    } 
                    if (png) {
                        filename = paste(path,fileprefix,sub(" ","_",i),".png",sep="")
                        png(filename=filename,
                            width=500, height=500, pointsize=pointsize)
                        cat("Created File: ",filename,"\n")
                    }
                    if (!postscript && !png) {
                         get(getOption("device"))(width=7,height=7)
                    }
                        
                    plot(0,type="n",
                        xlim=c(lld - 0.5, lhd + 2),
                        ylim= c(-0.1, hr + 0.2),
                        xlab=paste("Decadic Logarithm of the dose in ", unit),    
                        ylab="Normalized response")
                }
                if (!overlay) legend(lpos, i,lty = 1, col = color, inset=0.05)
                tmp$dosefactor <- factor(tmp$dose)  # necessary because the old
                                                    # factor has all levels, not 
                                                    # only the ones tested with
                                                    # this substance
                # Plot the data, if requested
                if (dtype != "none") {
                    if (dtype == "raw") {
                        points(log10(tmp$dose),tmp$response,col=color)
                    } else {
                        splitresponses <- split(tmp$response,tmp$dosefactor)
                        means <- sapply(splitresponses,mean)
                        lengths <- sapply(splitresponses,length)
                        vars <- sapply(splitresponses,var)
                        standarddeviations <- sqrt(vars)
                    }
                    if (dtype == "std")
                    {
                        tops <- means + standarddeviations
                        bottoms <- means - standarddeviations
                    }
                    if (dtype == "conf")
                    {
                        confidencedeltas <- qt((1 + alpha)/2, lengths - 1) * sqrt(vars) 
                        tops <- means + confidencedeltas
                        bottoms <- means - confidencedeltas
                    }
                    if (dtype != "raw")
                    {
                        x <- log10(as.numeric(levels(tmp$dosefactor)))
                        segments(x,bottoms,x,tops,col=color)
                        points(x,means,col=color)
                        smidge <- 0.05
                        segments(x - smidge,bottoms,x + smidge,bottoms,col=color)
                        segments(x - smidge,tops,x + smidge,tops,col=color)
                    }
                }

                # Plot the fits, if there are any
                fits <- subset(drresults,Substance == i)
                nf <-  length(fits$Substance)  # number of fits to plot
                if (nf > 0) {
                    for (j in 1:nf)
                    {
                        logEC50 <- fits[j,"logEC50"]
                        mtype <- as.character(fits[j, "mtype"])
                        if (mtype == "probit") {
                            scale <- fits[j,"b"]
                            plot(function(x) pnorm(-x,-logEC50,scale),lld - 0.5, lhd + 2, add=TRUE,col=color)
                        }
                        if (mtype == "logit") {
                            scale <- fits[j,"b"]
                            plot(function(x) plogis(-x,-logEC50,scale),lld - 0.5, lhd + 2, add=TRUE,col=color)
                        }
                        if (mtype == "weibull") {
                            location <- fits[j,"a"]
                            shape <- fits[j,"b"]
                            plot(function(x) pweibull(-x+location,shape),lld - 0.5, lhd + 2, add=TRUE,col=color)
                        }
                        if (mtype == "linlogit") {
                            plot(function(x) linlogitf(10^x,1,fits[j,"c"],fits[j,"logEC50"],fits[j,"b"]),
                                lld - 0.5, lhd + 2,
                                add=TRUE,col=color)
                        }
                    }
                }
                if (!overlay && (postscript || png)) dev.off()
            } else {
                cat("No data for ",i,"\n")
            }
        }
    }
    if (overlay) legend(lpos, dsubstances,lty = 1, col = colors, inset=0.05)
    if (overlay && (postscript || png)) {
        if (devoff) {
            dev.off()
        }
    }
}

checkplate <- function(plate,db="cytotox")
{
    library(RODBC) 
    channel <- odbcConnect(db,uid="cytotox",pwd="cytotox",case="tolower")

    if (db == "cytotox") {
        responsetype <- "viability"
        testtype <- "celltype"
    } else {
        responsetype <- "activity"
        testtype <- "enzyme"
    }
        
    platequery <- paste("SELECT experimentator,substance,",testtype,",conc,unit,",responsetype,",performed,ok",
        "FROM ",db," WHERE plate=", plate)

    controlquery <- paste("SELECT type,response FROM controls WHERE plate=",plate)
    
    platedata <- sqlQuery(channel,platequery)
    controldata <- sqlQuery(channel,controlquery)

    odbcClose(channel)

    if (length(platedata$experimentator) < 1) {
        cat("There is no response data for plate ",plate," in database ",db,"\n")
    } else {
        platedata$experimentator <- factor(platedata$experimentator)
        platedata$type <- factor(platedata[[testtype]])
        platedata$substance <- factor(platedata$substance)
        platedata$unit <- factor(platedata$unit)
        platedata$performed <- factor(platedata$performed)
        platedata$ok <- factor(platedata$ok)
        
        blinds <- subset(controldata,type=="blind")
        controls <- subset(controldata,type=="control")
        
        numberOfBlinds <- length(blinds$response)
        numberOfControls <- length(controls$response)
        meanOfBlinds <- mean(blinds$response)
        meanOfControls <- mean(controls$response)
        stdOfBlinds <- sd(blinds$response)
        stdOfControls <- sd(controls$response)
        percentstdOfcontrols <-stdOfControls *100/meanOfControls
        
        cat("Plate ",plate," from database ",db,"\n",
            "\tExperimentator: ",levels(platedata$experimentator),"\n",
            "\tType(s): ",levels(platedata$type),"\n",
            "\tPerformed on : ",levels(platedata$performed),"\n",
            "\tSubstance(s): ",levels(platedata$substance),"\n",
            "\tConcentration unit: ",levels(platedata$unit),"\n",
            "\tOK: ",levels(platedata$ok),"\n",
            "\t\tNumber \tMean \t\tStandard Deviation \t% Standard Deviation \n",
            "\tblind\t",numberOfBlinds,"\t",meanOfBlinds,"\t",stdOfBlinds,"\n",
            "\tcontrol\t",numberOfControls,"\t",meanOfControls,"\t",stdOfControls,"\t\t",percentstdOfcontrols,"\n")
        
        par(ask=TRUE)
        
        boxplot(blinds$response,controls$response,names=c("blinds","controls"),ylab="Response",main=paste("Plate ",plate))
        
        drdata <- platedata[c(2,4,6)]
        drdata$substance <- factor(drdata$substance)
        substances <- levels(drdata$substance)
       
        plot(log10(drdata$conc),drdata$viability,
            xlim=c(-2.5, 4.5), 
            ylim= c(-0.1, 2), 
            xlab=paste("decadic logarithm of the concentration in ",levels(platedata$unit)),
            ylab=responsetype)
        
        drdatalist <- split(drdata,drdata$substance)
        
        for (i in 1:length(drdatalist)) {
            points(log10(drdatalist[[i]]$conc),drdatalist[[i]][[responsetype]],col=i);
        }

        legend("topleft",substances, pch=1, col=1:length(substances), inset=0.05)
        title(main=paste("Plate ",plate," - ",levels(platedata$experimentator)," - ",levels(platedata$type)))
    }
}

checksubstance <- function(substance,db="cytotox",experimentator="%",celltype="%",enzymetype="%",whereClause="1",ok="%") 
{
    library(RODBC) 
    channel <- odbcConnect(db,uid="cytotox",pwd="cytotox",case="tolower")

    if (db == "cytotox") {
        responsetype <- "viability"
        testtype <- "celltype"
        type <- celltype
    } else {
        responsetype <- "activity"
        testtype <- "enzyme"
        type <- enzymetype
    }
    query <- paste("SELECT experimentator,substance,",testtype,",plate,conc,unit,",responsetype,",ok",
        " FROM ",db," WHERE substance LIKE '",
        substance,"' AND experimentator LIKE '",
        experimentator,"' AND ",testtype," LIKE '",
        type,"' AND ",
        whereClause," AND ok LIKE '",ok,"'",sep="")

    data <- sqlQuery(channel,query)
    odbcClose(channel)
    
    data$experimentator <- factor(data$experimentator)    
    data$substance <- factor(data$substance)
    substances <- levels(data$substance)    
    data$type <- factor(data[[testtype]])                
    data$plate <- factor(data$plate)                        
    plates <- levels(data$plate)
    concentrations <- split(data$conc,data$conc)
    concentrations <- as.numeric(names(concentrations))
    data$unit <- factor(data$unit)                        
    data$ok <- factor(data$ok)
    
    if (length(plates)>6) {
        palette(rainbow(length(plates)))      
    }
 
    plot(log10(data$conc),data[[responsetype]],
        xlim=c(-2.5, 4.5),                                                                  
        ylim= c(-0.1, 2),                                                                 
        xlab=paste("decadic logarithm of the concentration in ",levels(data$unit)),    
        ylab=responsetype)  
        
    platelist <- split(data,data$plate)
   
    for (i in 1:length(platelist)) {    
        points(log10(platelist[[i]]$conc),platelist[[i]][[responsetype]],col=i);          
    }       
    
    legend("topleft", plates, pch=1, col=1:length(plates), inset=0.05)
    title(main=paste(substance," - ",levels(data$experimentator)," - ",levels(data$type)))
 
    cat("Substanz ",substance,"\n",
        "\tExperimentator(s):",levels(data$experimentator),"\n",
        "\tType(s):\t",levels(data$type),"\n",
        "\tSubstance(s):\t",levels(data$substance),"\n",
        "\tPlate(s):\t",plates,"\n\n")
}

Contact - Imprint