5
我正在創建自定義學習器，特別是我試圖在mlr框架內使用h2o機器學習算法。 h2o.deeplearning函數的'hidden'參數是我想要調整的整數向量。在mlr中調整整數矢量
makeRLearner.classif.h2o_dl = function() {
makeRLearnerClassif(
cl = "classif.h2o_dl",
package = "h2o",
par.set = makeParamSet(
makeDiscreteLearnerParam(id = "activation",
values = c("Rectifier", "Tanh", "TanhWithDropout", "RectifierWithDropout", "Maxout", "MaxoutWithDropout")),
makeNumericLearnerParam(id = "epochs", default = 10, lower = 1),
makeNumericLearnerParam(id = "rate", default = 0.005, lower = 0, upper = 1),
makeIntegerVectorLearnerParam(id = "hidden", default = c(100,100)),
makeDiscreteLearnerParam(id = "loss", values = c("Automatic",
"CrossEntropy", "Quadratic", "Absolute", "Huber"))
),
properties = c("twoclass", "multiclass", "numerics", "factors", "prob","missings"),
name = "Deep Learning Neural Network with h2o",
short.name = "h2o_deeplearning_classif",
note = "tbd"
)
}
trainLearner.classif.h2o_dl = function(.learner, .task,.subset,.weights=NULL, ...) {
f = getTaskFormula(.task)
data = getTaskData(.task, .subset)
data_h2o <- as.h2o(data,
destination_frame = paste0(
"train_",
format(Sys.time(), "%m%d%y_%H%M%S")))
h2o::h2o.deeplearning(x = getTaskFeatureNames(.task),
y = setdiff(names(getTaskData(.task)),
getTaskFeatureNames(.task)),
training_frame = data_h2o, ...)
}
predictLearner.classif.h2o_dl = function(.learner, .model, .newdata, predict.method = "plug-in", ...) {
data <- as.h2o(.newdata,
destination_frame = paste0("pred_",
format(Sys.time(), "%m%d%y_%H%M%S")))
p = predict(.model$learner.model, newdata = data, method = predict.method, ...)
if (.learner$predict.type == "response")
return(as.data.frame(p)[,1]) else return(as.matrix(as.numeric(p))[,-1])
}
我試圖通過makeDiscreteParam功能的手段調諧經由網格搜索參數「隱藏」：我以下面的方式定義的「隱藏」參數
library(mlr)
library(h2o)
h2o.init()
lrn.h2o <- makeLearner("classif.h2o_dl")
n <- getTaskSize(sonar.task)
train.set = seq(1, n, by = 2)
test.set = seq(2, n, by = 2)
mod.h2o = train(lrn.h2o, sonar.task, subset = train.set)
pred.h2o <- predict(mod.h2o,task= sonar.task, subset = train.set)
ctrl = makeTuneControlGrid()
rdesc = makeResampleDesc("CV", iters = 3L)
ps = makeParamSet(
makeDiscreteParam("hidden", values = list(c(10,10),c(100,100))),
makeDiscreteParam("rate", values = c(0.1,0.5))
)
res = tuneParams("classif.h2o_dl", task = sonar.task, resampling = rdesc,par.set = ps,control = ctrl)
這導致警告消息
Warning messages:
1: In checkValuesForDiscreteParam(id, values) :
number of items to replace is not a multiple of replacement length
2: In checkValuesForDiscreteParam(id, values) :
number of items to replace is not a multiple of replacement length
和ps看起來是這樣的：
ps
Type len Def Constr Req Tunable Trafo
hidden discrete - - 10,100 - TRUE -
rate discrete - - 0.1,0.5 - TRUE -
這不會導致將隱藏參數調整爲向量。我也嘗試過其他特殊的構造函數（例如makeNumericVectorParam），它們也不起作用。 有沒有人在調整（整數）載體在mlr的經驗，可以給我一個提示？
這聽起來像你需要在這裏使用'makeNumericVectorParam'。你能分享你嘗試過的代碼嗎？ –
我剛剛添加了完整的代碼 –
嗯，如果你想嘗試一下這些特定的值，我會引入一個虛擬參數，它只是一個值列表中的索引，用於在學習器的包裝器中嘗試和檢查/轉換它。 –