为什么我的 BMI 计算器总是返回用户输入的体重？

如何解决为什么我的 BMI 计算器总是返回用户输入的体重？

def get_values()
  puts("Please enter your height in metres.")
  height = gets.chomp.to_i
  puts("Please enter your weight in kilograms.")
  weight = gets.chomp.to_i
  bmi = ((weight).to_f / (height * height).to_f)
  puts("Your BMI is: ")
  puts bmi.to_s
end

def main()
  puts("Welcome to the BMI calculator. Would you like to continue?")
  answer = gets.chomp
  if (answer == "yes" or "Yes")
    get_values()
  else
    ("Understandable,have a nice day.")
  end
end

main()

如果您运行此程序，您将看到您输入的任何体重值都将作为 BMI 返回。为什么是这样？我简直无法理解为什么会这样。显然，我是 Ruby 的新手。以前，我在计算中没有 .to_f 转换，但这也返回了“重量”的用户输入值。请帮忙。

编辑：虽然我非常感谢下面重写我的代码，因为它与我通常的编码风格非常不同，我已经用下面的答案解决了这个问题 - 我只是在 .to_f 中进行了转换错误的地方。这个效果很好，精确到小数点后 14 位！

def get_values()
  puts("Please enter your height in metres.")
  height = gets.to_f
  puts("Please enter your weight in kilograms.")
  weight = gets.to_f
  bmi = ((weight) / (height * height))
  puts("Your BMI is: ")
  puts bmi.to_s
end

def main()
  puts("Welcome to the BMI calculator. Would you like to continue?")
  answer = gets.chomp
  if (answer == "yes" or "Yes")
    get_values()
  else
    ("Understandable,have a nice day.")
  end
end

main()

编辑：我不记得我是否更改了与计算相关的任何内容，但代码已再次更新。

def get_values()
  puts("Please enter your height in metres.")
  height = gets.to_f
  puts("Please enter your weight in kilograms.")
  weight = gets.to_f
  bmi = ((weight) / (height * height))
  puts("Your BMI is: ")
  puts bmi.to_s
  return bmi
end

def harsh_truths()
  bmi = get_values()
  if (bmi < 18.5)
    puts("You are underweight.")
  elsif (bmi > 18.5) and (bmi < 25.0)
    puts("You are a healthy weight.")
  elsif (bmi > 25) and (bmi < 30)
    puts("You are overweight.")
  elsif (bmi > 30)
    puts("You are obese.")
  end
end

def main()
  puts("Welcome to the BMI calculator. Would you like to continue?")
  answer = gets.chomp
  if (answer == "yes") or (answer == "Yes")
    harsh_truths()
  else
    ("Understandable,have a nice day.")
  end
end

main()

以上是我一直提到的“更新代码”。当我添加使用英制值计算 BMI 的选项时，我希望能再次见到你们。

解决方法

这是相同代码的固定的、更惯用的 Ruby 版本：

# Define a generic method to grab input
def ask(prompt)
  puts prompt
  gets.to_f
end

# Loop while more input is available
loop do
  # puts doesn't always use brackets,it's subjective. You can,but
  # in many cases they're omitted for simplicity.
  puts("Welcome to the BMI calculator. Would you like to continue?")

  case (gets.chomp)
  when /\An/i # Anything that "starts with" (\A) "n" + case insensitive (/i)
    puts "Understandable,have a nice day."
    break
  end

  # Get some input
  height = ask("Please enter your height in metres.")
  weight = ask("Please enter your weight in kilograms.")

  # Notice how if they're already float this becomes super easy
  bmi = weight / (height * height)

  # Use string interpolation,automatic .to_s conversion happens.
  puts "Your BMI is: #{bmi}"
end

,

只需将高度和 weight 更改为 float 如下：

height = gets.chomp.to_f

weight = gets.chomp.to_f