A couple of years ago, we looked at theExcel SUBTOTAL function, and saw how you could allow users to select the function they want. In the example shown below, the total formulas are controlled by the drop down list at the top of the sheet. Today, we'll use a similar technique to ...
The aggregate function is more difficult to use, but it is included in the base R installation and does not require the installation of another package. # Get a count of number of subjects in each category (sex*condition) cdata <- aggregate(data["subject"], by=data[c("sex","condition"...
The aggregate function is more difficult to use, but it is included in the base R installation and does not require the installation of another package. #Get a count of number of subjectsineach category (sex*condition)cdata <- aggregate(data["subject"], by=data[c("sex","condition...
x:指定R 对象by:指定分组元素列表FUN:指定函数来计算统计汇总 要了解更多可选参数,请在控制台中使用以下命令: help("aggregate") 范例1: # Using state.x77 and state.region dataset # Compute the mean of the states in state.x77 # grouped by state.region variables aggregate(state.x77, list(region...
R语言中aggregate函数 R语⾔中aggregate函数 前⾔ 这个函数的功能⽐较强⼤，它⾸先将数据进⾏分组（按⾏），然后对每⼀组数据进⾏函数统计，最后把结果组合成⼀个⽐较nice的表格返回。根据数据对象不同它有三种⽤法，分别应⽤于数据框（data.frame）、公式（formula）和时间序列（ts）：aggreg...
an R object. by a list of grouping elements, each as long as the variables in the data frame x. The elements are coerced to factors before use. #by这个就是按某个变量来分类,这个变量要转成因子类型,并且和数据的长度要相同。 FUN a function to compute the summary statistics which can be ap...
一个R对象。 by:a list of grouping elements, each as long as the variables in the data frame x. The elements are coerced to factors before use. 一列分组元素,每个与数据框x中的变量等长。元素在使用之前被强制为因子。 FUN:a function to compute the summary statistics which can be applied to ...
Note A syntax error is returned if the column argument passed in is of a non-numeric or non-date type.The label portion is optional and provides a more readable alias for the label. If you do not include an alias label, Windows Search transforms the function and column name into a ...
The following is an example of a user-defined aggregate function that concatenates a set of string values taken from a column in a table: [C#] Copy using System; using System.Data; using Microsoft.SqlServer.Server; using System.Data.SqlTypes; using System.IO; using System.Text; [Serializabl...
A neuronal microtubule-interacting agent, NAPVSIPQ, reduces tau pathology and enhances cognitive function in a mouse model of Alzheimer's disease. Either as a cause or an effect, tau becomes hyperphosphorylated and aggregates into paired helical filaments that comprise the tangles. To assess whether...