Question

我有一个数据框操作问题。

我想找到数据框的子集＆＃34; data1＆＃34;每个col的总和等于另一个数据帧＆＃34; data2＆＃34;。

这是我的代码：

public byte[] saveImage() {
    //reder the view once, in software.
    buildDrawingCache();
    //get the rendered bitmap
    Bitmap bitmap = getDrawingCache();

    ByteArrayOutputStream bos = new ByteArrayOutputStream();
    bitmap.compress(Bitmap.CompressFormat.JPEG, 100 /*ignored for PNG*/, bos);
    byte[] data = bos.toByteArray();
    //destroy the drawing cache, to clear up the memory
    destroyDrawingCache();

    try {
        bos.flush();
        bos.close();
    } catch (IOException e) {
        e.printStackTrace();
    }

    if (data == null) {
        Log.e(TAG, "data in touchview before save clicked is null");
    } else {
        Log.e(TAG, "data in touchview before saved clicked is not null and has length + " + data.length);
    }

    return data;
}

我想知道其他任何算法是否有帮助？

谢谢！

Answer 1

此解决方案仅考虑您要从任意两行计算总和的方案。如果要测试其他行号，则需要通过更改combn函数中的数字来创建这些组合。 final_data是最终输出。如果有多个匹配项，您可能希望将final_data保留为列表。

# Prepare example datasets
AA<-c(2,3,1,4,9)
BB<-c(5,13,9,1,2)

A1<-c(5)
B1<-c(18)

data1<-data.frame(AA,BB)
data2<-data.frame(A1,B1)

# Load packages
library(tidyverse)

# Use combn to find out all the combination of row number
row_indices <- as.data.frame(t(combn(1:nrow(data1), 2)))

# Prepare a list of data frame. Each data frame is one row from row_indices
row_list <- row_indices %>%
  rowid_to_column() %>%
  split(f = .$rowid)

# Based on row_list to subset data1
sub_list <- map(row_list, function(dt){
  temp_data <- data1 %>% filter(row_number() %in% c(dt$V1, dt$V2))
  return(temp_data)
})

# Calcualte the sum of each data frame in sub_list
sub_list2 <- map(sub_list, function(dt){
  dt2 <- dt %>% 
    summarise_all(funs(sum(.))) %>%
    setNames(c("A1", "B1"))
  return(dt2)
})

# Compare each data frame in sub_list2 with data2
# Find the one that is the same and store the logical results in result_indices
result_indices <- map_lgl(sub_list2, function(dt) setequal(dt, data2))

# Get the final output
final_data <- sub_list[result_indices][[1]]

final_data
  AA BB
1  2  5
2  3 13

R：子集数据帧条件对子集数据帧的总和

1 个答案: