Ruby on Rails BigDecimal not adding properly

Question

I am trying to make a form, in which a user can input a number (withdraw/deposit) and then the amount will show in a post. But, whatever I tried, the BigDecimals do not add up.

class MicropostsController < ApplicationController
  before_action :logged_in_user, only: [:create, :destroy]

  def create
    @micropost = current_user.microposts.build(micropost_params)
    if @micropost.save
      flash[:success] = "Micropost created!"
      current_user.update_attributes(deposit: deposits(@micropost.deposit), 
                                     withdraw: withdrawals(@micropost.withdraw),
                                     total: totals(@micropost.deposit, @micropost.withdraw)) 
      redirect_to root_url
    else
      @feed_items = []
      render 'static_pages/home'
    end
  end

  def deposits(money)
    return current_user.deposit + BigDecimal(money)
  end

  def withdrawals(money)
    return current_user.withdraw + BigDecimal(money)
  end

  def totals(dep, wit)
    return current_user.total + BigDecimal(dep) - BigDecimal(wit)
  end

  private

    def micropost_params
    params.require(:micropost).permit(:content, :deposit, :withdraw)
  end
end

So what happens is that when @micropost.deposit = 2.3 and @micropost.withdraw = 2.4, Ruby on Rails seems to round both to the nearest whole number, and the output is 4.0.

Here is also my form

<%= form_for(@micropost) do |f| %>
  <%= render 'shared/error_messages', object: f.object %>
  <div class="field">
    <%= f.text_area :content, placeholder: "Compose new micropost..." %>
  </div>
  <div class="field">
    <%= f.text_field :deposit, placeholder: "Deposit. Input only positive numbers, e.g. 0.00" %>
  </div>
  <div class="field">
    <%= f.text_field :withdraw, placeholder: "Withdraw: Input only positive numbers, e.g. 0.00" %>
  </div>
  <%= f.submit "Post", class: "btn btn-primary" %>
<% end %>

Answer 1

I think you have a 2 part problem:

1. BigDecimal - requires a precision if you don't want it to round to an integer, so BigDecimal(1.7,1) is 2 and BigDecimal(1.7,2) is 1.7
2. The datatypes on the withdraw and deposit fields may be integer and not decimal