Example 2: for-Loop Over Rows of Data Frame It is also possible to apply for-loops to loop through the rows of a data frame. Example 2 explains how to use thenrow functionfor this task. First, let’s replicate our data: data2<-data# Replicate example data Now, we can apply the fo...
Before you do so, note that you can get the number of rows in your data frame using nrow(stock). Then, you can create a sequence to loop over from 1:nrow(stock). for (row in 1:nrow(stock)) { price <- stock[row, "apple"] date <- stock[row, "date"] if(price > 117) { ...
在您的代码中,您正在重新定义每个循环,因此最终结果与使用i = 4运行一次代码相同 为了获得所需的结果,可以意识到数据帧是一个等于length-rows的列表,因此我们可以使用lapply。
Delete duplicate rows 大寫 小寫 首字母大寫 替換全部 表格生成器 Follow Me 捐贈者複製到剪切板下載 MarkdownMagicLaTeXSQLHTMLCSVExcelJSONJSONLinesASCIIMediaWikiAsciiDocTracWikiQlikDAXFirebaseYAMLXMLJiraTextilereStructuredTextPHPRubyASPActionScriptBBCodePDFJPEGPNGTOMLINIAvroProtobufRDataFramePandasDataFrameRDFMATLAB ...
我想得到dataframe中特定列的平均值,并将这些平均值存储在R中的向量中。 列的特定变量名存储在向量中。对于那些特定的变量(取决于用户输入),我想计算平均值并将其存储在一个向量中,我可以在这个向量上循环,然后在代码的另一部分使用它。 我尝试了以下操作,e.g.: ...
transposed_data$Variable <- names(mydata)[-1] # loop through and fill in the rest. For each original column, copy its values over. for (i in 2:ncol(mydata)) { transposed_data[i-1, -1] <- as.numeric(mydata[, i]) } # final dataframe print(transposed_data) Variable A1 A2 A3...
1. Function ‘apply’ on a simple matrix: a. Get the following matrix of 5 rows and call it ‘mymatrix’ b. Get the mean of each row c. Get the mean of each column d. Sort the columns in ascending order 2. Using ‘lapply’ on a data.frame ‘mtcars’ a. Use three ‘apply’...
R -在一个for循环中，如果一个 Dataframe 遍历列df[[i]]，我如何为每个循环打印列df[[i]]的名称...
第二个便是foreach循环,需要加载foreach包。Foreach provides an elegant way to loop through multiple elements of another object (such as a vector, matrix, data frame, or iterator), evaluate an expression for each element, and return the results.下面是foreach函数的原型。
问RStudio/ R-为列中的值与字符串完全匹配的行创建新的df (需要更快的速度)EN背景： 业务发展需要...