Python Progress Bar ValueError: Value out of range

Question

我的进度条达到 100% 然后抛出错误

from progressbar import Percentage, ProgressBar,Bar,ETA

pbar = ProgressBar(widgets=[Bar('=', '[', ']'), ' ',
                                            Percentage(), ' ',
                                            ETA()]).start()
            for i,row in enumerate(cursor):

               '''
                do some work here

               ''' 

                pbar.update(i)

这是我得到的

Traceback (most recent call last):=========================] 100% ETA:  0:00:00
  File "X:\src\dbtest\PymssqlCheck.py", line 27, in <module>
    fiddler.getRows(condetails, dbdetails, 'compliance', 'doctable', '*', '1000')
  File "X:\src\utilities\fiddler.py", line 45, in getRows
    pbar.update(i)
  File "X:\Anaconda2\lib\site-packages\progressbar\__init__.py", line 271, in update
    raise ValueError('Value out of range')
ValueError: Value out of range

为什么到了100%就失败了？我正在使用

https://github.com/niltonvolpato/python-progressbar

我什至试过

 i=0                                
            for row in cursor:

                ''' do some work here ''' 

                if i < numrows:
                    pbar.update(i)
                    i=i+1

但我仍然得到同样的错误

编辑

我尝试了 Tomasz Jakub Rup 的回答

pbar = ProgressBar(widgets=[Bar('=', '[', ']'), ' ',
                                        Percentage(), ' ',
                                        ETA()])
for row in pbar(cursor):
    ''' do some work here '''

我得到

File "X:\fiddler.py", line 41, in getRows
    for row in pbar(cursor):
  File "X:\Anaconda2\lib\site-packages\progressbar\__init__.py", line 180, in __next__
    if self.start_time is None: self.start()
  File "X:\Anaconda2\lib\site-packages\progressbar\__init__.py", line 311, in start
    self.update(0)
  File "X:\Anaconda2\lib\site-packages\progressbar\__init__.py", line 283, in update
    self.fd.write(self._format_line() + '\r')
  File "X:\Anaconda2\lib\site-packages\progressbar\__init__.py", line 243, in _format_line
    widgets = ''.join(self._format_widgets())
  File "X:\Anaconda2\lib\site-packages\progressbar\__init__.py", line 223, in _format_widgets
    widget = format_updatable(widget, self)
  File "X:\Anaconda2\lib\site-packages\progressbar\widgets.py", line 38, in format_updatable
    if hasattr(updatable, 'update'): return updatable.update(pbar)
  File "X:\Anaconda2\lib\site-packages\progressbar\widgets.py", line 184, in update
    return '%3d%%' % pbar.percentage()
  File "X:\Anaconda2\lib\site-packages\progressbar\__init__.py", line 208, in percentage
    return self.currval * 100.0 / self.maxval
TypeError: unsupported operand type(s) for /: 'float' and 'classobj'

知道为什么吗？

Answer 1

因为进度条默认满了100。如果你有 N 个步骤，你应该指定一个 maxval=N。

例如：

from progressbar import Percentage, ProgressBar,Bar,ETA

N = 300

pbar = ProgressBar(widgets=[Bar('=', '[', ']'), ' ', Percentage(), ' ', ETA()],
                   maxval=N).start()

for i in range(N+1):
    pbar.update(i)

Answer 2

尝试：

pbar = ProgressBar(widgets=[Bar('=', '[', ']'), ' ',
                                        Percentage(), ' ',
                                        ETA()])
for row in pbar(cursor.fetchall()):
    ''' do some work here '''

在这种情况下您不需要更新 pbar 也不需要开始和完成 pbar。

Answer 3

David 和 Tomasz，你们两个都非常接近。有效的解决方案是

pbar = ProgressBar(widgets=[Bar('>', '[', ']'), ' ',
                                            Percentage(), ' ',
                                            ETA()],maxval=someMaxValue)
            for row in pbar(cursor):
                ''' do some work '''

Answer 4

progress = ProgressBar(maxval=my.objects.count() or None).start() 为我修复

参考：https://github.com/niltonvolpato/python-progressbar/issues/36

Python Progress Bar ValueError: Value out of range

Python Progress Bar ValueError: Value out of range

python

progress-bar