Question

我有一个程序可以找到一些数据并对数据运行一个基本的数学函数，但是当我运行它时，我收到以下错误：ValueError: invalid literal for float(): Timestep:。错误发生在我调用map(float,line.split()[1:])的行中。

有谁知道为什么以及如何解决此错误。

#!/usr/bin/python


l=[]
with open("movie.xyz") as f:
   line = f.next()
   nat = int(line.split()[0])
   print nat
   f.next()# skip headers
   for line in f:
       if line.strip():
           l.append(map(float,line.split()[1:]))  # make all values floats   
#print l[0][0]
b = 0
a = 1
for b in range(55):
    for a in range(b+1,56):
    import operator
    import numpy as np
    #vector1 = l[b]
    vector1 = (l[b][0],l[b][1],l[b][2])
    vector2 = (l[a][0],l[a][1],l[a][2])
    #print('vector 1 = %' % vector1)
    #print('vector 1 = (%f,%f,%f)' % vector1)
    #print vector2
    x = vector1
    y = vector2
    vector3 = list(np.array(x) - np.array(y))
    #print vector3
    dotProduct = reduce( operator.add, map( operator.mul, vector3, vector3))    
    dp = dotProduct**.5
    print dp

前几行数据看起来像：

2805
Atoms. Timestep: 0
Cu 46.7176 27.1121 27.1121
Cu 43.2505 36.0618 32.4879
Cu 43.3392 36.0964 28.9236
Cu 43.2509 37.8362 27.1091
Cu 43.3406 36.0958 25.2957
Cu 43.2582 36.0629 21.737
Cu 43.2505 32.4879 36.0618

Answer 1

插入

import pdb; pdb.set_trace()

在此行之前，看看是什么给了你line.split()[1:]

pdb =提示调试器：https://docs.python.org/2/library/pdb.html

或者这样做：

if line.strip():
    try:
        l.append(map(float,line.split()[1:]))  
    except ValueError:
        print "Value error at: ", line.split()[1:]

＃

使此代码工作添加此功能：

def foo(value):
    try:
        result = float(value)
    except ValueError:
        print "cant parse %r into float" %value
        result = None
    return result

并替换该行：

l.append(map(float,line.split()[1:]))

为：

l.append(map(foo, line.split()[1:]))

ValueError：float（）的无效文字：Timestep：

1 个答案:

＃