python - 从输入的数组中减去数字

Question

我对 Python 非常陌生，并试图弄清楚如何减去用户输入的数组中的数字。例如，在我的程序的早期，我有：`

peakone = raw_input("Where is the next large peak?: ")
next_peak.append(peakone)
peaktwo = raw_input("Where is the next large peak?: ")
next_peak.append(peaktwo)

现在我想从 peaktwo 中减去 peakone 并将这个值保存为第三个。如果有的话，最好的方法是什么？

Answer 1

设置next_peak为list

将输入转换为int或float

next_peak = []
peakone = raw_input("Where is the next large peak?: ")
next_peak.append(int(peakone))
peaktwo = raw_input("Where is the next large peak?: ")
next_peak.append(int(peaktwo))
print next_peak[0] - next_peak[1] 

可以int根据float需要更改

Answer 2

你可以这样做：

peakthree = float(peaktwo) - float(peakone)

你得到的raw_input是一个字符串，所以你需要把它转换成数字类型，比如floator int。考虑像这样编写代码：

def get_next_peak():
    return float(raw_input("Where is the next large peak?: "))

next_peak = []
next_peak.append(get_next_peak())
next_peak.append(get_next_peak())
next_peak.append(next_peak[1] - next_peak[0])