Question

python程序读取和输出数据

如图所示，现在想输出附件中cpress值开始不等于零和重新全部等于零时的“step time ”值，也就是想输出附件中“step time= 1.0001E-04 ”和“step time=2.500E-04” 这两个结果，说来惭愧，这段代码研究了半天，采用了好多方法都不行，请好心人帮忙给段代码！急求，谢谢！

Answer 1

class StepTime:
def __init__(self,name):
self.name=name
self.values=[]
def close(self):
if sum(self.values)==0.0:
print "all zero:",self.name
def put(self,value):
self.values.append(float(value))
if len(values)==1:
print "not zero:",self.name

import re,os
lasttime=None
for line in open("filename","rt"):
if line.startswith("step"):
if lasttime:lasttime.close()
name=line[len('step time='):].strip()
lasttime=StepTime(name)
else:
lasttime.put(line[line.find("=")+1:].strip())
lasttime.close()

完成了，就这东西。似乎StepTime这个类就是一个简单的状态机吧。

Answer 2

定义一个“状态机”类，用正则表达式解析数据文件的各行，
将解析的行信息提交到状态机进行状态变化的控制

Answer 3

f = open("文件名","r")
result = []

for line in f:
sline = line.strip()
if sline == "step time= 1.0001E-04" or sline == “step time= 2.500E-04”:
result.append(sline.split(" ")[-1])

f.close()
print result

Answer 4

import re

s = open('i.txt', 'r').read()
p = 'step time= (.*)'
r = re.split(p, s, re.M)

prev = None
it = iter(r[1:])
for x,y in zip(it, it):
p = '.*cpress=(.*)'
r = re.findall(p,y)
r[:] = [float(t) for t in r]
v = max(r)
if prev == 0 and v > prev or v == 0 and prev > 0:
print x
prev = v