本文实例讲述了Python显示进度条的方法，是Python程序设计中非常实用的技巧。分享给大家供大家参考。具体方法如下：

首先，进度条和一般的print区别在哪里呢？

答案就是print会输出一个\n，也就是换行符，这样光标移动到了下一行行首，接着输出，之前已经通过stdout输出的东西依旧保留，而且保证我们在下面看到最新的输出结果。

进度条不然，我们必须再原地输出才能保证他是一个进度条，否则换行了怎么还叫进度条？

最简单的办法就是，再输出完毕后，把光标移动到行首，继续在那里输出更长的进度条即可实现，新的更长的进度条把旧的短覆盖，就形成了动画效果。

可以想到那个转义符了吧，那就是\ r。

转义符r就可以把光标移动到行首而不换行，转义符n就把光标移动到行首并且换行。

在python中，输出stdout(标准输出)可以使用sys.stdout.write
例如：

 
 
 
 
 

Python

 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
#!/usr/bin/env python
# -*- coding=utf-8 -*-
#Using GPL v2
#Author: ihipop@gmail.com
##2010-10-27 22:07
"""
Usage:
Just A Template
"""
from __future__ import division
 
import sys,time
j = '#'
if __name__ == '__main__':
    for i in range(1,61):
        j += '#'
        sys.stdout.write(str(int((i/60)*100))+'%  ||'+j+'->'+"\r")
        sys.stdout.flush()
        time.sleep(0.5)
print

第二种思路是用转义符\b
转义符\b是退格键，也就是说把输出的光标往回退格子，这样就可以不用+=了，例如：

 
 
 
 
 

Python

 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
#!/usr/bin/env python
# -*- coding=utf-8 -*-
#Using GPL v2
#Author: ihipop@gmail.com
#2010-10-27 22:07
"""
Usage:
Just A Template
"""
from __future__ import division
 
import sys,time
if __name__ == '__main__':
    for i in range(1,61):
        sys.stdout.write('#'+'->'+"\b\b")
        sys.stdout.flush()
        time.sleep(0.5)
print

光标回退2格，写个#再回退，再写，达到增长的目的了

不过写这么多似乎是废话，在耳边常常听到一句话：那就是不要重复造轮子。实际上python有丰富发lib帮你实现这个东西，你完全可以把心思放在逻辑开发上而不用注意这些小细节的百度云网盘搜索

下面要介绍的就是这个类“progressbar”(http://code.google.com/p/python-progressbar/)，使用easy_install可以方便的安装这个类库，其实就一个文件，拿过来放到文件同一个目录下面也直接可以import过来

如下图所示：

下面就是基本使用举例：

 
 
 
 
 
 

Python

 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
#!/usr/bin/env python
# -*- coding=utf-8 -*-
#Using GPL v2
#Author: ihipop@gmail.com
#2010-10-27 22:53
"""
Usage:
Just A Template
"""
from __future__ import division
 
import sys,time
from progressbar import *
total = 1000
 
#基本用法
progress = ProgressBar()
for i in progress(range(total)):
  time.sleep(0.01)
 
pbar = ProgressBar().start()
for i in range(1,1000):
    pbar.update(int((i/(total-1))*100))
    time.sleep(0.01)
pbar.finish()
 
#高级用法
widgets = ['Progress: ', Percentage(), ' ', Bar(marker=RotatingMarker('>-=')),
           ' ', ETA(), ' ', FileTransferSpeed()]
pbar = ProgressBar(widgets=widgets, maxval=10000000).start()
for i in range(1000000):
  # do something
  pbar.update(10*i+1)
  time.sleep(0.0001)
pbar.finish()

官方示例:http://code.google.com/p/python-progressbar/source/browse/progressbar/examples.py

 
 
 
 
 
 

Python

 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
# coding:utf-8
import sys
import time
from progressbar import AnimatedMarker, Bar, BouncingBar, Counter, ETA, \
    FileTransferSpeed, FormatLabel, Percentage, \
    ProgressBar, ReverseBar, RotatingMarker, \
    SimpleProgress, Timer
 
examples = []
 
def example(fn):
    try:
        name = 'Example %d' % int(fn.__name__[7:])
    except:
        name = fn.__name__
 
    def wrapped():
        try:
            sys.stdout.write('Running: %s\n' % name)
            fn()
            sys.stdout.write('\n')
        except KeyboardInterrupt:
            sys.stdout.write('\nSkipping example.\n\n')
 
    examples.append(wrapped)
    return wrapped
 
@example
def example0():
    pbar = ProgressBar(widgets=[Percentage(), Bar()], maxval=300).start()
    for i in range(300):
        time.sleep(0.01)
        pbar.update(i + 1)
    pbar.finish()
 
@example
def example1():
    widgets = ['Test: ', Percentage(), ' ', Bar(marker=RotatingMarker()),
               ' ', ETA(), ' ', FileTransferSpeed()]
    pbar = ProgressBar(widgets=widgets, maxval=10000000).start()
    for i in range(1000000):
        # do something
        pbar.update(10 * i + 1)
    pbar.finish()
 
@example
def example2():
    class CrazyFileTransferSpeed(FileTransferSpeed):
        """It's bigger between 45 and 80 percent."""
 
        def update(self, pbar):
            if 45 < pbar.percentage() < 80:
                return 'Bigger Now ' + FileTransferSpeed.update(self, pbar)
            else:
                return FileTransferSpeed.update(self, pbar)
 
    widgets = [CrazyFileTransferSpeed(), ' <<<', Bar(), '>>> ',
               Percentage(), ' ', ETA()]
    pbar = ProgressBar(widgets=widgets, maxval=10000000)
    # maybe do something
    pbar.start()
    for i in range(2000000):
        # do something
        pbar.update(5 * i + 1)
    pbar.finish()
 
@example
def example3():
    widgets = [Bar('>'), ' ', ETA(), ' ', ReverseBar('<')]
    pbar = ProgressBar(widgets=widgets, maxval=10000000).start()
    for i in range(1000000):
        # do something
        pbar.update(10 * i + 1)
    pbar.finish()
 
@example
def example4():
    widgets = ['Test: ', Percentage(), ' ',
               Bar(marker='0', left='[', right=']'),
               ' ', ETA(), ' ', FileTransferSpeed()]
    pbar = ProgressBar(widgets=widgets, maxval=500)
    pbar.start()
    for i in range(100, 500 + 1, 50):
        time.sleep(0.2)
        pbar.update(i)
    pbar.finish()
 
@example
def example5():
    pbar = ProgressBar(widgets=[SimpleProgress()], maxval=17).start()
    for i in range(17):
        time.sleep(0.2)
        pbar.update(i + 1)
    pbar.finish()
 
@example
def example6():
    pbar = ProgressBar().start()
    for i in range(100):
        time.sleep(0.01)
        pbar.update(i + 1)
    pbar.finish()
 
@example
def example7():
    pbar = ProgressBar()  # Progressbar can guess maxval automatically.
    for i in pbar(range(80)):
        time.sleep(0.01)
 
@example
def example8():
    pbar = ProgressBar(maxval=80)  # Progressbar can't guess maxval.
    for i in pbar((i for i in range(80))):
        time.sleep(0.01)
 
@example
def example9():
    pbar = ProgressBar(widgets=['Working: ', AnimatedMarker()])
    for i in pbar((i for i in range(50))):
        time.sleep(.08)
 
@example
def example10():
    widgets = ['Processed: ', Counter(), ' lines (', Timer(), ')']
    pbar = ProgressBar(widgets=widgets)
    for i in pbar((i for i in range(150))):
        time.sleep(0.1)
 
@example
def example11():
    widgets = [FormatLabel('Processed: %(value)d lines (in: %(elapsed)s)')]
    pbar = ProgressBar(widgets=widgets)
    for i in pbar((i for i in range(150))):
        time.sleep(0.1)
 
@example
def example12():
    widgets = ['Balloon: ', AnimatedMarker(markers='.oO<a href="http://www.jobbole.com/members/weiboyes8848">@*</a> ')]
    pbar = ProgressBar(widgets=widgets)
    for i in pbar((i for i in range(24))):
        time.sleep(0.3)
 
@example
def example13():
    # You may need python 3.x to see this correctly
    try:
        widgets = ['Arrows: ', AnimatedMarker(markers='←↖↑↗→↘↓↙')]
        pbar = ProgressBar(widgets=widgets)
        for i in pbar((i for i in range(24))):
            time.sleep(0.3)
    except UnicodeError:
        sys.stdout.write('Unicode error: skipping example')
 
@example
def example14():
    # You may need python 3.x to see this correctly
    try:
        widgets = ['Arrows: ', AnimatedMarker(markers='◢◣◤◥')]
        pbar = ProgressBar(widgets=widgets)
        for i in pbar((i for i in range(24))):
            time.sleep(0.3)
    except UnicodeError:
        sys.stdout.write('Unicode error: skipping example')
 
@example
def example15():
    # You may need python 3.x to see this correctly
    try:
        widgets = ['Wheels: ', AnimatedMarker(markers='◐◓◑◒')]
        pbar = ProgressBar(widgets=widgets)
        for i in pbar((i for i in range(24))):
            time.sleep(0.3)
    except UnicodeError:
        sys.stdout.write('Unicode error: skipping example')
 
@example
def example16():
    widgets = [FormatLabel('Bouncer: value %(value)d - '), BouncingBar()]
    pbar = ProgressBar(widgets=widgets)
    for i in pbar((i for i in range(180))):
        time.sleep(0.05)
 
@example
def example17():
    widgets = [FormatLabel('Animated Bouncer: value %(value)d - '),
               BouncingBar(marker=RotatingMarker())]
 
    pbar = ProgressBar(widgets=widgets)
    for i in pbar((i for i in range(180))):
        time.sleep(0.05)
 
@example
def example18():
    widgets = [Percentage(),
               ' ', Bar(),
               ' ', ETA(),
               ' ', AdaptiveETA()]
    pbar = ProgressBar(widgets=widgets, maxval=500)
    pbar.start()
    for i in range(500):
        time.sleep(0.01 + (i < 100) * 0.01 + (i > 400) * 0.9)
        pbar.update(i + 1)
    pbar.finish()
 
@example
def example19():
    pbar = ProgressBar()
    for i in pbar([]):
        pass
    pbar.finish()
 
try:
    for example in examples:
        example()
except KeyboardInterrupt:
    sys.stdout('\nQuitting examples.\n')

再发一个类：

 
 
 
 
 
 

Python

 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
#!/usr/bin/env python
# -*- coding=utf-8 -*-
#Using GPL v2
#Author: ihipop@gmail.com
#2010-10-30 13:59
"""
Usage:
Just A Template
"""
class progressbarClass:
    def __init__(self, finalcount, progresschar=None):
        import sys
        self.finalcount=finalcount
        self.blockcount=0
        #
        # See if caller passed me a character to use on the
        # progress bar (like "*").  If not use the block
        # character that makes it look like a real progress
        # bar.
        #
        if not progresschar: self.block=chr(178)
        else:                self.block=progresschar
        #
        # Get pointer to sys.stdout so I can use the write/flush
        # methods to display the progress bar.
        #
        self.f=sys.stdout
        #
        # If the final count is zero, don't start the progress gauge
        #
        if not self.finalcount : return
        self.f.write('\n------------------- % Progress -------------------\n')
        return
 
    def progress(self, count):
        #
        # Make sure I don't try to go off the end (e.g. >100%)
        #
        count=min(count, self.finalcount)
        #
        # If finalcount is zero, I'm done
        #
        if self.finalcount:
            percentcomplete=int(round(100*count/self.finalcount))
            if percentcomplete < 1: percentcomplete=1
        else:
            percentcomplete=100
 
        #print "percentcomplete=",percentcomplete
        blockcount=int(percentcomplete/2)
        #print "blockcount=",blockcount
        if blockcount > self.blockcount:
            for i in range(self.blockcount,blockcount):
                self.f.write(self.block)
                self.f.flush()
 
        if percentcomplete == 100: self.f.write("\n")
        self.blockcount=blockcount
        return
 
if __name__ == "__main__":
    from time import sleep
    pb=progressbarClass(8,"*")
    count=0
    while count<9:
        count+=1
        pb.progress(count)
        sleep(0.2)

另外，python cookbook中11.1节也提供了一个不错的进度条类，代码如下：

 
 
 
 
 
 

Python

 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
import sys
 
class progressbar(object):
 
    def __init__(self, finalcount, block_char='.'):
        self.finalcount = finalcount
        self.blockcount = 0
        self.block = block_char
        self.f = sys.stdout
        if not self.finalcount:
            return
        self.f.write('\n------------------ % Progress -------------------1\n')
        self.f.write('  1  2  3  4  5  6  7  8  9  0\n')
        self.f.write('----0----0----0----0----0----0----0----0----0----0\n')
 
    def progress(self, count):
        count = min(count, self.finalcount)
        if self.finalcount:
            percentcomplete = int(round(100.0 * count / self.finalcount))
            if percentcomplete < 1:
                percentcomplete = 1
        else:
            percentcomplete = 100
        blockcount = int(percentcomplete // 2)
        if blockcount <= self.blockcount:
            return
        for i in range(self.blockcount, blockcount):
            self.f.write(self.block)
        self.f.flush()
        self.blockcount = blockcount
        if percentcomplete == 100:
            self.f.write("\n")
 
if __name__ == "__main__":
    from time import sleep
    pb = progressbar(8, "*")
    for count in range(1, 9):
        pb.progress(count)
        sleep(0.2)
    pb = progressbar(100)
    pb.progress(20)
    sleep(0.3)
    pb.progress(47)
    sleep(0.3)
    pb.progress(90)
    sleep(0.3)
    pb.progress(100)
    print "testing 1:"
    pb = progressbar(1)
    pb.progress(1)

运行结果如下图所示：

Python中如何写控制台进度条的整理的更多相关文章

  1. Python中使用print打印进度条

    import time for i in range(0,101,2): time.sleep(0.1) char_num = i//2 #打印多少个'*' per_str = '\r%s%% : % ...

  2. 用python的time库写一个进度条

    运算符 算数运算 如a=10,b=20 +两个数相加 a+b=30 -两个数相减 a-b=-10 两个数相乘 a****b =200 /两个数相除b/a=2 %取模,并返回余数b%a=0 幂,a*** ...

  3. 用C#实现控制台进度条

    在写一些简单的控制台测试程序时,经常希望能够在程序运行的过程中实现进度条的功能以便查看程序运行的速度或者进度.本文以C#为例,实现简单的控制台进度条,以供大家参考(本文底部附下载地址). 1.实现效果 ...

  4. [c#]控制台进度条的示例

    看到[vb.net]控制台进度条的示例 感觉很好玩,翻译成C#版. using System; using System.Collections.Generic; using System.Linq; ...

  5. Python 控制台进度条的实现

    进行爬虫等耗时的任务时,有时会想在控制台输出进度条,以显示当前任务进度.这里总结了两种方法. 方法1:使用tqdm模块 示例代码: from time import sleep from tqdm i ...

  6. [ python ] 使用sys模块实现进度条

    在写网络IO传输的时候, 有时候需要进度条来显示当前传输进度,使用 sys 模块就可以实现: sys.stdout.write() 这个函数在在控制台输出字符串不会带任何结尾,这就意味着这个输出还没有 ...

  7. 用 Python 给程序加个进度条，让你的看起来更炫酷？

    对于开发或者运维来说,使用 Python 去完成一些跑批任务,或者做一些监控事件是非常正常的情况.那么如何有效地监控任务的进度?除了在任务中加上 Log 外,还能不能有另一种方式来了解任务进展到哪一步 ...

  8. css3实现loading效果--当页面加载过程中显示Loading的进度条，全部加载完成之后进度条消失

    一个页面等图片资源全部加载完成,会需要很长时间,用户体验会很差,所以我们需要loading来掩盖这个漫长的过程! emmm,定时器?写个定时器还要清除,万一造成内存泄露?定时器之间还会互相影响,呼呼呼 ...

  9. ruby 编写控制台进度条

    ruby 中,$stdout.flush 让控制台当前行内容可以重写,以此我们可以做出进度条的效果. def set_progress(index, char = '*') print (char * ...

随机推荐

  1. Android开发UI之android:gravity / android:layout_Gravity，android:padding / android:layout_margin属性区分

    android:gravity / android:layout_Gravity区别: android:gravity 是设置该view里面的内容相对于该view的位置,例如设置button里面的te ...

  2. BZOJ_1096_[ZJOI2007]_仓库建设_(斜率优化动态规划+单调队列+特殊的前缀和技巧)

    描述 http://www.lydsy.com/JudgeOnline/problem.php?id=1096 有\(n\)个工厂,给出第\(i\)个工厂的到1号工厂的距离\(x[i]\),货物数量\ ...

  3. c语言_文件操作_FILE结构体解释_涉及对操作系统文件FCB操作的解释_

    1. 文件和流的关系 C将每个文件简单地作为顺序字节流(如下图).每个文件用文件结束符结束,或者在特定字节数的地方结束,这个特定的字节数可以存储在系统维护的管理数据结构中.当打开文件时,就建立了和文件 ...

  4. Java线程之Phaser

    Phaser是一个灵活的线程同步工具,他包含了CyclicBarrier和CountDownLatch的相关功能 首先,来看一下如何用Phaser替代CountDownLatch.对于CountDow ...

  5. HTTP协议分析及攻防方法

    HTTP协议简介 应用层协议,无状态协议(可设定为维持TCP连接,但服务器端的资源会释放).默认HTTP的端口号为80,HTTPS的端口号为443. 基于HTTP协议的客户机访问包括4个过程,分别是建 ...

  6. å∫ç∂´ƒ©˙ˆ∆˚¬µ˜øπœ®ß†¨√∑≈¥Ω who know?

    ´é∑w∑w∑wqq¡œœ∑åååß∂˚¬∆¬˚∆˙ß∂ƒµ˜∫√ç≍Ωåœ∑´®†¥¨ˆøπ“‘æ…¬˚∆˙©ƒ∂ßåΩ≍ç≍ç√∫˜µ≤≥÷÷¡™£¢∞§§¶••ªº–≠«``¡™£¢∞§¶•ªº ...

  7. HW2.15

    public class Solution { public static void main(String[] args) { double rate = 0.05; double balance ...

  8. Pascal <-> C/C++ 转换简明教程

    在OI的学习中,阅读多种语言的能力是很重要的. 本文就着眼于让大家最快地掌握这两种语言间的转换方法. 程序主结构 C/C++ Pascal 主程序(即开始执行的程序段)和其他函数.过程本质上都属于函数 ...

  9. 问题-Delphi在多线程中使用其他窗体上的控件,报“尚未调用CoInitialize”解决方法

    1.uses ActiveX; 2. procedure HLCJ.Execute;begin    CoInitialize(nil);    //要使用的控件    CoUninitialize; ...

  10. nyoj 27 水池数目

    水池数目 时间限制:3000 ms  |  内存限制:65535 KB 难度:4   描述 南阳理工学院校园里有一些小河和一些湖泊,现在,我们把它们通一看成水池,假设有一张我们学校的某处的地图,这个地 ...