Question

我的表就像这样

# group rows based on cumsum with reset
cumsum_with_reset_group <- function(x, threshold) {
  cumsum <- 0
  group <- 1
  result <- numeric()

  for (i in 1:length(x)) {
    cumsum <- cumsum + x[i]

    if (cumsum > threshold) {
      group <- group + 1
      cumsum <- x[i]
    }

    result = c(result, group)

  }

  return (result)
}

# cumsum with reset
cumsum_with_reset <- function(x, threshold) {
  cumsum <- 0
  group <- 1
  result <- numeric()

  for (i in 1:length(x)) {
    cumsum <- cumsum + x[i]

    if (cumsum > threshold) {
      group <- group + 1
      cumsum <- x[i]
    }

    result = c(result, cumsum)

  }

  return (result)
}

# use functions above as window functions inside mutate statement
df %>% group_by() %>%
  mutate(
    cumsum_10 = cumsum_with_reset(value, 10),
    group_10 = cumsum_with_reset_group(value, 10)
  ) %>% 
  ungroup()

我想这样显示（通过添加行）

S.No.   Name    Amount
1       Mike    200
2       Jason   150
3       Mike    100
4       Andy    300
5       Jason   200

我的代码是 -

S.No.   Name    Amount
1       Mike    300
2       Jason   350
3       Andy    300

如果使用Ruby on Rails名称字段相同，如何添加金额？

Answer 1

使用架构，数据和＆amp ;;编辑答案码。

这是表格架构＆amp;记录

mysql> select * from users;
+----+-----------+------------+------------+
| id | full_name | created_at | updated_at |
+----+-----------+------------+------------+
|  1 | Gowtham   | NULL       | NULL       |
|  2 | Mike      | NULL       | NULL       |
|  3 | Jason     | NULL       | NULL       |
|  4 | Andy      | NULL       | NULL       |
+----+-----------+------------+------------+

mysql> select * from data;
+----+--------------+------------+--------+------------+------------+
| id | from_user_id | to_user_id | amount | created_at | updated_at |
+----+--------------+------------+--------+------------+------------+
|  1 |            1 |          2 |    200 | NULL       | NULL       |
|  2 |            1 |          2 |    100 | NULL       | NULL       |
|  3 |            1 |          2 |    150 | NULL       | NULL       |
|  4 |            1 |          2 |    200 | NULL       | NULL       |
|  5 |            1 |          3 |    150 | NULL       | NULL       |
|  6 |            1 |          3 |    200 | NULL       | NULL       |
|  7 |            1 |          4 |    300 | NULL       | NULL       |
+----+--------------+------------+--------+------------+------------+

现在，这里是一个代码，用于查找Gowtham向其他人完成的所有转移。你可以将它放在你的控制器中

 @result = Data.where(:from_user_id => 1).select("users.full_name, SUM(data.amount) as total").joins("INNER JOIN users ON users.id = data.to_user_id").group(:to_user_id)

您可以遍历@result并在视图中显示

<table class="table">
    <thead>
        <tr>
            <th>S.No.</th>
            <th>Name</th>
            <th>Amount</th>
        </tr>
    </thead>
    <tbody>
    <% @result.each_with_index do |tc, index| %>
      <% begin %>
        <tr>
            <td><%=index+1%></td>
            <td><%=tc.full_name%></td>
            <td><%=tc.total%></td>
        </tr>
      <% rescue %>
      <% next %>
      <% end %>
    <% end %>
  </tbody>
</table>

希望这有帮助

Answer 2

您可以尝试使用此功能获取名称及其总金额

Data.select("name, sum(amount) as amount").group(:name)

如果行中有相同的数据（Rails），如何添加行数据

2 个答案: