劃分兩個變量返回0

Question

當我設置爲ratio = needed/count該函數可以工作，但我需要一個百分比，所以當我將它設置爲ratio = count/needed時，理論上它應該返回一個小數點，但它返回0.我在做什麼錯誤？我需要它返回正確的數字來設置寬度百分比。

def percent_bar(piece, options={}) 
    count = file.total_count 
    needed = HD::Application.config.files_needed 
    ratio = count/needed 
    percent = ratio * 100 
    s = "<div class='progress'>" 
    s += "<div class='progress-bar' role='progressbar' aria-valuemax='#{needed}' aria-valuenow='#{count}' aria-valuemin='0' style='width: #{ratio}%;'>" 
    s += "<span class='sr-only'>#{count} of #{needed}</span>" 
    s += "</div>" 
    s += "</div>" 

    return s 

    end 

Answer 1

您正在分割兩個整數值，所以結果將始終爲整數。

執行此代替：

count/needed.to_f 

實施例：

count = 1 
needed = 2 
count/needed 
# => 0 
count/needed.to_f # type conversion to float 
# => 0.5 

Answer 2

這是因爲正在執行整數除法。使用to_f轉換爲float。

ratio = count/needed.to_f