【发布时间】：2020-04-12 08:36:42
【问题描述】：
我有一个简单的类，其中一种方法是获取指定值的列表的索引，因为它包含该值。 方法是下面类中的get_index_at_time(time)
class TimeStamp:
def __init__(self):
self.timeList = []
self.indexList = []
self.localDate = None
def add(self, inTime, idx):
if self.localDate is None:
# Get todays date
self.localDate = datetime.datetime.now()
# Fix timeList with time adjusted to inTime
thisTime = create_timestamp(self.localDate, inTime)
self.timeList.append(thisTime)
self.indexList.append(idx)
def get_time_at_index(self, ix):
if len(self.timeList) > ix and 0 <= ix:
return self.timeList[ix]
def get_index_at_time(self, inTime):
ix = self.timeList.index(inTime)
if ix:
return self.indexList[ix]
else:
return -1
由于列表中第一个元素的某些奇怪原因而失败，例如index 0 但我已经检查过具有相同数据的列表上的 index 方法是否适用于 index 0 它只有在类中使用时才会表现得很奇怪。
运行脚本会给出：
$ python3 simple_index_test.py ==================================================== Testing list index method for dbgList: Test passed ==================================================== Start testing TimeStamp.get_time_at_index Test passed ==================================================== Start testing TimeStamp.get_index_at_time - Test Failed for time stamp: 2020-04-12 01:01:01 ==================================================== Comparing the values in dbgList with idx1.TimeList Test passed ====================================================
代码如下：
import datetime
def create_timestamp(localDate, inTime):
timeString = localDate.strftime('%Y-%m-%d') + ' ' + inTime
return datetime.datetime.strptime(timeString, '%Y-%m-%d %H:%M:%S')
class TimeStamp:
def __init__(self):
self.timeList = []
self.indexList = []
self.localDate = None
def add(self, inTime, idx):
if self.localDate is None:
# Get todays date
self.localDate = datetime.datetime.now()
# Fix timeList with time adjusted to inTime
thisTime = create_timestamp(self.localDate, inTime)
self.timeList.append(thisTime)
self.indexList.append(idx)
def get_time_at_index(self, ix):
if len(self.timeList) > ix and 0 <= ix:
return self.timeList[ix]
def get_index_at_time(self, inTime):
ix = self.timeList.index(inTime)
if ix:
return self.indexList[ix]
else:
return -1
log1 = [
[0.123, '01:01:01', 0],
[0.134, '01:01:02', 1],
[0.145, '01:01:03', 1],
[0.156, '01:01:04', 2],
[0.167, '01:01:05', 2],
[0.178, '01:01:06', 2],
[0.189, '01:01:07', 3],
]
def main():
# Get todays date
localDate = datetime.datetime.now()
idx1 = TimeStamp()
# debug list for testing the index method directly
dbgList = []
# Fill idx1
for ix,val in enumerate(log1):
idx1.add(val[1], ix)
# Debugging why test fails, create an identical list of same time stamp as in the TimeStamp class
thisTime = create_timestamp(localDate, val[1])
dbgList.append(thisTime)
print('====================================================')
print('Testing list index method for dbgList:')
testPassed = True
for ix, val in enumerate(dbgList):
rx = dbgList.index(val)
if rx != ix:
print('List index() method failed match for: ' + str(val))
testPassed = False
if testPassed:
print('Test passed')
# Test method get_time_at_index
print('====================================================')
print('Start testing TimeStamp.get_time_at_index')
testPassed = True
# Loop over all elements in log1
for ix,val in enumerate(log1):
thisTime = idx1.get_time_at_index(ix)
# Create the expected time stamp
expectedTime = create_timestamp(localDate, val[1])
if thisTime != expectedTime:
print(' - Test Failed for index: ' + str(ix))
testPassed = False
if testPassed:
print('Test passed')
# Test method get_index_at_time
print('====================================================')
print('Start testing TimeStamp.get_index_at_time')
testPassed = True
# Loop over all elements in log1
for ix,val in enumerate(log1):
# Create the time we want to get index for
wantedTime = create_timestamp(localDate, val[1])
thisIndex = idx1.get_index_at_time(wantedTime)
if thisIndex != ix:
print(' - Test Failed for time stamp: ' + str(wantedTime))
testPassed = False
if testPassed:
print('Test passed')
print('====================================================')
print('Comparing the values in dbgList with idx1.TimeList')
testPassed = True
for ix, val in enumerate(dbgList):
idxTimeStamp = idx1.timeList[ix]
if idxTimeStamp != val:
print(' - Test Failed for time stamps (dbg) (idx1.timeList): ' + str(val) + ' ' + str(idxTimeStamp))
testPassed = False
if testPassed:
print('Test passed')
print('====================================================')
if __name__ == "__main__":
main()
【问题讨论】：
-
if ix:不适用于列表中索引 0 处的元素。
标签： python list python-datetime