我正在编写一个程序，允许用户输入日期并输入他们在特定日期所需的股票信息类型。所有股票信息和日期都在一个单独的CSV文件中。我的程序不会运行，我觉得我错过了一些东西。这是一个类，我不想使用ruby的CSV类。
以下是此文件的示例：
date,open,high,low,close,volume,changed,changep,adjclose,tradeval,tradevol
2013-10-07,23.84,23.90,23.80,23.89,3522559,-0.16,-0.67%,23.89,83992937.36,8462
2013-10-04,24.18,24.18,23.90,24.05,33274615,-0.05,-0.21%,24.05,800232596.05,74361
2013-10-03,24.22,24.25,23.84,24.10,37466161,-0.23,-0.95%,24.10,902130194.02,95122
这是我的计划：
#open the file
data = File.open("data.csv","r+")
#make an empty hash
stocks = {}
contents = data.readlines
data.close
#this add quotes between each line
contents.collect! do |x|
x.chomp
end
#this splits up each in into its own array
contents.collect! do |x|
x.split(',')
end
contents.each do |x|
stocks[x[0]] = x
end
puts "This program has all the General Electic stock information from November 27, 1960 to October 8 2013. Please enter the date you would like to find the stock information of like this: 1997-10-30 (year-month-day)."
#prompt user for the date of the stock info they would like to find
date = gets.chomp
data = stocks[date]
puts "Please enter what information about the stock you would like to know: open, high, low, close, volume, changed, percent change,adjusted closing, trade value, or trade volume. Please put a underscore in place of all spaces."
#get an input for what type of stock information the user would like
input = gets.chomp
#elsif statement to give the user the info they need based on what stock info they want
if input == open
puts "The open of your stock is: #{data[1]}"
elsif input == high
puts "The high of your stock is: #{data[2]}"
elsif input == low
puts "The low of your stock is: #{data[3]}"
elsif input == close
puts "The close of your stock is: #{data[4]}"
elsif input == volume
puts "The volume of your stock is: #{data[5]}"
elsif input == changed
puts "The volume of your stock is: #{data[6]}"
elsif input == percent_change
puts "The percent change of your stock is: #{data[7]}"
elsif input == adjusted_closing
puts "The open adjusted closing of your stock is: #{data[8]}"
elsif input == trade_value
puts "The trade value of your stock is: #{data[9]}"
else input == trade_volume
puts "The trade volume of your stock is: #{data[10]}"
end
答案 0 :(得分：0)
这是你的代码清理了一下：
require 'csv'
puts "This program has all the General Electric stock information from November
27, 1960 to October 8 2013. Please enter the date you would like to find the
stock information of like this: 1997-10-30 (year-month-day)."
date = gets.chomp
puts "Please enter what information about the stock you would like to know:
open, high, low, close, volume, changed, percent change,adjusted closing, trade
value, or trade volume. Please put a underscore in place of all spaces."
input = gets.chomp
CSV.foreach(
'test.csv',
:headers => true,
:return_headers => false
) do |row|
next unless row['date'] == date
if input == 'open'
puts "The open of your stock is: #{ row['open'] }"
elsif input == 'high'
puts "The high of your stock is: #{ row['high'] }"
elsif input == 'low'
puts "The low of your stock is: #{ row['low'] }"
elsif input == 'close'
puts "The close of your stock is: #{ row['close'] }"
elsif input == 'volume'
puts "The volume of your stock is: #{ row['volume'] }"
elsif input == 'changed'
puts "The volume of your stock is: #{ row['changed'] }"
elsif input == 'percent_change'
puts "The percent change of your stock is: #{ row['percent_change'] }"
elsif input == 'adjusted_closing'
puts "The open adjusted closing of your stock is: #{ row['adjusted_closing'] }"
elsif input == 'trade_value'
puts "The trade value of your stock is: #{ row['trade_value'] }"
elseif input == 'trade_volume'
puts "The trade volume of your stock is: #{ row['trade_volume'] }"
else
puts "An unknown option was entered."
end
end
使用这些输入：
1997-10-30
open
返回：
The open of your stock is: 23.84
The open of your stock is: 24.18
The open of your stock is: 24.22
使用Ruby的CSV类。它已经编写好了，它已经过调试和测试，所以你不必重新发明那个轮子。您可以告诉它使用CSV文件的第一行作为标题，以及是否应该返回它们。此外，它可以将一行数据作为数组或散列返回。将其作为哈希值取回对于您想要做的事情非常有用。
以下是一些重构，向您展示如何简化和删除冗余代码：
require 'csv'
puts "This program has all the General Electric stock information from November
27, 1960 to October 8 2013. Please enter the date you would like to find the
stock information of like this: 1997-10-30 (year-month-day)."
date = gets.chomp
puts "Please enter what information about the stock you would like to know:
open, high, low, close, volume, changed, percent change,adjusted closing, trade
value, or trade volume. Please put a underscore in place of all spaces."
input = gets.chomp
CSV.foreach(
'test.csv',
:headers => true,
:return_headers => false
) do |row|
next unless row['date'] == date
case input
when 'open'
puts "The open of your stock is: #{ row['open'] }"
when 'high'
puts "The high of your stock is: #{ row['high'] }"
when 'low'
puts "The low of your stock is: #{ row['low'] }"
when 'close'
puts "The close of your stock is: #{ row['close'] }"
when 'volume'
puts "The volume of your stock is: #{ row['volume'] }"
when 'changed'
puts "The volume of your stock is: #{ row['changed'] }"
when 'percent_change'
puts "The percent change of your stock is: #{ row['percent_change'] }"
when 'adjusted_closing'
puts "The open adjusted closing of your stock is: #{ row['adjusted_closing'] }"
when 'trade_value'
puts "The trade value of your stock is: #{ row['trade_value'] }"
when 'trade_volume'
puts "The trade volume of your stock is: #{ row['trade_volume'] }"
else
puts "An unknown option was entered."
end
end
此版本将if/elseif/else替换为case/when，这有助于简化逻辑，并为相同的输入返回相同的内容。
require 'csv'
puts "This program has all the General Electric stock information from November
27, 1960 to October 8 2013. Please enter the date you would like to find the
stock information of like this: 1997-10-30 (year-month-day)."
date = gets.chomp
puts "Please enter what information about the stock you would like to know:
open, high, low, close, volume, changed, percent change,adjusted closing, trade
value, or trade volume. Please put a underscore in place of all spaces."
input = gets.chomp
CSV.foreach(
'test.csv',
:headers => true,
:return_headers => false
) do |row|
next unless row['date'] == date
val = case input
when 'open'
'open'
when 'high'
'high'
when 'low'
'low'
when 'close'
'close'
when 'volume'
'volume'
when 'changed'
'changed'
when 'percent_change'
'percent_change'
when 'adjusted_closing'
'adjusted_closing'
when 'trade_value'
'trade_value'
when 'trade_volume'
'trade_volume'
else
puts "An unknown option was entered."
next
end
puts "The %s of your stock is: %s" % [val.gsub('_', ' '), row[val] ]
end
这建立在case语句的基础上，只返回了哪些更改，但也向我们展示了大量冗余。
require 'csv'
puts "This program has all the General Electric stock information from November
27, 1960 to October 8 2013. Please enter the date you would like to find the
stock information of like this: 1997-10-30 (year-month-day)."
date = gets.chomp
puts "Please enter what information about the stock you would like to know:
open, high, low, close, volume, changed, percent change, adjusted closing,
trade value, or trade volume. Please put a underscore in place of all spaces."
input = gets.chomp
CSV.foreach(
'test.csv',
:headers => true,
:return_headers => false
) do |row|
puts "The %s of your stock is: %s" % [input.gsub('_', ' '), row[input] ] if (row['date'] == date)
end
在此代码中删除冗余结果。