如何在R中創建循環以迭代地繪製數組元素？

Question

我正在嘗試創建一個循環以從之前創建的數組中提取數據，以便我可以使用提取的數據生成一個線圖。

到目前爲止，我一直在做手工用：

allweek1<-(data.frame(t_weekmean[,,1])) #which selects the date and generates the data frame I want to later format the date using 
week1<-stack(allweek1) #and then plot it using 
plot(week1$values,type="n", xlim=c(0,2),xlab="Weight (gr)",ylab="Rate (umol/L*gr)",main="All individuals and Treatments at all times") 
lines(week1$values[week1$ind=="X9"]~x,type="o",col="red") 
lines(week1$values[week1$ind=="X12"]~x,type="o",col="blue") 
lines(week1$values[week1$ind=="X15"]~x,type="o",col="green") 
lines(week1$values[week1$ind=="X18"]~x,type="o",col="purple"). 

我知道必須有使這變成一個循環，在這個例子中，我給短短兩週的一種方式，但我的數據去最多30個，手動操作會很麻煩，容易出錯。

這是起始陣列我有：

, , Week = 1 

     Temp 
variable  9  12  15  18 
    X0 100.000 100.000 100.000 100.000 
    X0.5 98.855 98.591 98.357 99.003 
    X1 98.004 97.804 97.638 98.299 
    X1.5 95.953 96.999 96.810 97.555 
    X2 95.235 96.078 95.346 96.665 

, , Week = 2 

     Temp 
variable  9  12  15  18 
    X0 100.000 100.000 100.000 100.000 
    X0.5 99.137 99.035 97.883 99.055 
    X1 98.420 98.298 96.459 97.765 
    X1.5 97.939 97.181 94.406 96.546 
    X2 96.998 96.237 91.906 95.263 

以下的數據幀，然後將其轉換爲一個堆版本：

  X9  X12  X15  X18 
X0 100.000 100.000 100.000 100.000 
X0.5 98.855 98.591 98.357 99.003 
X1 98.004 97.804 97.638 98.299 
X1.5 95.953 96.999 96.810 97.555 
X2 95.235 96.078 95.346 96.665 

，然後被用於繪製的代碼。

Answer 1

聽起來任務格：

X <- as.data.frame(as.table(t_weekmean), stringsAsFactors=FALSE, responseName="values") 
X$variable <- as.numeric(gsub("^X","",X$variable)) 
X$Temp <- as.numeric(X$Temp) 

require(lattice) 
xyplot(values~variable|Week, groups=Temp, X, type="o", as.table=TRUE, 
    xlab="Weight (gr)", ylab="Rate (umol/L*gr)", main="All individuals and Treatments at all times" 
) 

我重新創建數據：

t_weekmean <- structure(c(100, 98.855, 98.004, 95.953, 95.235, 100, 98.591, 97.804, 96.999, 96.078, 100, 98.357, 97.638, 96.81, 95.346, 100, 99.003, 98.299, 97.555, 96.665, 100, 99.137, 98.42, 97.939, 96.998, 
100, 99.035, 98.298, 97.181, 96.237, 100, 97.883, 96.459, 94.406, 91.906, 100, 99.055, 97.765, 96.546, 95.263, 99.9889679441867, 
98.8470416045204, 98.010997102523, 95.9636806506725, 95.235986063534, 100.00797414162, 98.5968712619705, 97.7984016535804, 96.9904933552904, 
96.0816877686208, 99.9946318131395, 98.3568674165109, 97.6357767063124, 96.8119443900658, 95.3441814383421, 99.989633272252, 99.0037062049508, 
98.3034580102509, 97.5568340624981, 96.6615796074679, 100.000379644977, 99.1375077671092, 98.4187321210541, 97.9350205929782, 97.0006243532971, 
100.003971157774, 99.0316462150477, 98.298322594611, 97.1782003010139, 96.239865449585, 100.002464797458, 97.8810655647218, 96.4592857614756, 
94.4099917372801, 91.9025173998885, 100.003642400375, 99.0529984607268, 97.76302246443, 96.5426428484451, 95.2658935513329), 
.Dim = c(5L, 4L, 4L), .Dimnames = structure(list(variable = c("X0", "X0.5", "X1", "X1.5", "X2"), 
Temp = c("9", "12", "15", "18"), Week = c("1", "2", "3", "4")), .Names = c("variable", "Temp", "Week")) 
) 

Answer 2

如果使用plyr，你可以用a_ply做到這一點：

a_ply(t_weekmean, 3, function(arrayforcurweek){ 
allweek1<-(data.frame(arrayforcurweek)) #which selects the date and generates the data frame I want to later format the date using 
week1<-stack(allweek1) #and then plot it using 
plot(week1$values,type="n", xlim=c(0,2),xlab="Weight (gr)",ylab="Rate (umol/L*gr)",main="All individuals and Treatments at all times") 
lines(week1$values[week1$ind=="X9"]~x,type="o",col="red") 
lines(week1$values[week1$ind=="X12"]~x,type="o",col="blue") 
lines(week1$values[week1$ind=="X15"]~x,type="o",col="green") 
lines(week1$values[week1$ind=="X18"]~x,type="o",col="purple") 
}) 

一樣，這一點，你只會看到過的最後一個圖形，因爲剩下的就是典型的覆蓋。所以，你可能要添加一個佈局聲明，或提供的圖表等

OK，一些更多的信息，按您的評論之間的停頓：

a_ply需要3個參數在這裏：首先一個要執行陣列事情，下一個'邊緣'，這意味着：我應該迭代哪個維度（這是'隱藏'循環），最後是一個對所有部分執行的函數。

所以會發生什麼：a_ply爲您的數組的第三維（因爲邊距== 3）採取所有可能的值，並運行它們（你可以在for循環中看到這是一個索引器i）。然後它將你的數組的部分作爲這些值中的每一個（類似t_weekmean[,,i]），並將其作爲第三個參數提供給函數（因此在此函數中，連續的邊際數組將稱爲arrayforcurweek）。

這種工作方式的問題在於圖形是快速連續生成的，所以如果您只是運行此代碼並查看圖像窗口，則應該只能看到第三維的最後一個值的圖形。如果你想看到他們所有的相鄰（儘管這會導致微小的圖表），你可以用類似這樣的前綴： 佈局（矩陣（1:30），nrow = 6） 這將導致屏幕將其分成30部分，以便每個小區都能在全屏中獲得自己的一部分。

我相信，如果你立即寫一個PDF或類似的文件，你不需要這個，但我沒有這方面的經驗。

這幫助你嗎？