blocks|key|1042142|text|如果希望结果为最接近的二进制浮点数，请使用float|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1042143|result+=+[float(x.strip('+"'))+for+x+in+A1]|code-block|syntax|javascript|1042144|如果希望准确地存储结果，请使用Decimal而不是float|1042145|from+decimal+import+Decimal
result+=+[Decimal(x.strip('+"'))+for+x+in+A1]|1042146|entityMap|0|LINK|mutability|MUTABLE|url|http://docs.python.org/library/decimal.html^0|L|5|0|0|F|7|P|5|F|7|0|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@$9|X|A|Y|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|Z|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|10|8|@$9|11|A|12|B|C]|$9|13|A|14|B|C]]|D|@$9|15|A|16|1|17]]|E|$]]|$1|M|3|N|5|H|7|18|8|@]|D|@]|E|$I|J]]|$1|O|3|-4|5|6|7|19|8|@]|D|@]|E|$]]]|P|$Q|$5|R|S|T|E|$U|V]]]]

If you want the result as the nearest binary floating point number use <code>float</code>:

<pre><code>result = [float(x.strip(' "')) for x in A1]
</code></pre>

If you want the result stored exactly use <a href="http://docs.python.org/library/decimal.html" rel="noreferrer"><code>Decimal</code></a> instead of <code>float</code>:

<pre><code>from decimal import Decimal
result = [Decimal(x.strip(' "')) for x in A1]
</code></pre>

blocks|key|827420|text|您将需要使用strip()，因为字符串中有额外的位。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|827421|A2+=+[float(x.strip('"'))+for+x+in+A1]|code-block|syntax|javascript|827422|entityMap^0|6|7|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|P|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|L|$]]

You will need to use <code>strip()</code> because of the extra bits in the strings.

<pre><code>A2 = [float(x.strip('"')) for x in A1]
</code></pre>

blocks|key|1042268|text|在列表理解中使用内置的float()函数。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1042269|A2+=+[float(v.replace('"','').strip())+for+v+in+A1]|offset|length|style|CODE|1042270|entityMap^0|0|0|1F|0^^$0|@$1|2|3|4|5|6|7|J|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|K|8|@$D|L|E|M|F|G]]|9|@]|A|$]]|$1|H|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|I|$]]

use the built in float() function in a list comprehension.

<code>A2 = [float(v.replace('"','').strip()) for v in A1]</code>

blocks|key|827538|text|A2+=+[float(x.strip('"'))+for+x+in+A1]可以工作，@Jake，但是有不必要的0|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|827539|entityMap^0|0|12|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|K|8|@]|D|@]|E|$]]]|G|$]]

<code>A2 = [float(x.strip('"')) for x in A1]</code> works, @Jake , but there are unnecessary 0s

blocks|key|1042386|text|如果要将字符串转换为浮点型：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1042387|import+re
A1+=+['+"29.0"+','+"65.2"+','+"75.2"+']
float_values+=+[float(re.search(r'\d%2B.\d%2B',number).group())+for+number+in+A1]
print(float_values)
>>>+[29.0,+65.2,+75.2]|code-block|syntax|javascript|1042388|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

If you are converting string to float:

<pre><code>import re
A1 = [' "29.0" ',' "65.2" ',' "75.2" ']
float_values = [float(re.search(r'\d+.\d+',number).group()) for number in A1]
print(float_values)
&gt;&gt;&gt; [29.0, 65.2, 75.2]
</code></pre>

blocks|key|1042474|text|在Python中，有两种浮点数据类型Float和Decimal。用例取决于您希望在程序中使用的小数精度。Float很快，Decimal很精确。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1042475|要将字符串转换为浮点数，只需执行以下操作|1042476|import+decimal
float('1.2')
decimal.Decimal('1.2')|code-block|syntax|javascript|1042477|分析Float和Decimal对象|1042478|>>>+import+sys
>>>+from+decimal+import+Decimal

>>>+num+=+'1.2'

>>>+float(num)
1.2

>>>+Decimal(num)
Decimal('1.2')


>>>+#+Precision
>>>+float(1.2)
1.2

>>>+Decimal(1.2)
Decimal('1.1999999999999999555910790149937383830547332763671875')


>>>+#+Memory+usage
>>>+sys.getsizeof(Decimal(num))
104

>>>+sys.getsizeof(float(num))
24


>>>+#+Performance
>>>+%25timeit+float(num)
140+ns+±+2.27+ns+per+loop+(mean+±+std.+dev.+of+7+runs,+10000000+loops+each)

>>>+%25timeit+Decimal(num)
192+ns+±+9.42+ns+per+loop+(mean+±+std.+dev.+of+7+runs,+1000000+loops+each)|1042479|在您的特定情况下，您可以使用@Mark+Byer解决方案。|1042480|entityMap^0|I|5|O|7|1G|5|1O|7|0|0|0|2|5|8|7|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@$9|V|A|W|B|C]|$9|X|A|Y|B|C]|$9|Z|A|10|B|C]|$9|11|A|12|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|13|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|14|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|15|8|@$9|16|A|17|B|C]|$9|18|A|19|B|C]]|D|@]|E|$]]|$1|O|3|P|5|J|7|1A|8|@]|D|@]|E|$K|L]]|$1|Q|3|R|5|6|7|1B|8|@]|D|@]|E|$]]|$1|S|3|-4|5|6|7|1C|8|@]|D|@]|E|$]]]|T|$]]

In Python there are two floating point datatypes <code>Float</code> and <code>Decimal</code>. The use case depends on the precision of decimal you want in your program. <code>Float</code> is quick and <code>Decimal</code> is precise.
To convert a string to a floating point number just do
<pre><code>import decimal
float('1.2')
decimal.Decimal('1.2')
</code></pre>
Analysing <code>Float</code> and <code>Decimal</code> objects
<pre><code>&gt;&gt;&gt; import sys
&gt;&gt;&gt; from decimal import Decimal

&gt;&gt;&gt; num = '1.2'

&gt;&gt;&gt; float(num)
1.2

&gt;&gt;&gt; Decimal(num)
Decimal('1.2')


&gt;&gt;&gt; # Precision
&gt;&gt;&gt; float(1.2)
1.2

&gt;&gt;&gt; Decimal(1.2)
Decimal('1.1999999999999999555910790149937383830547332763671875')


&gt;&gt;&gt; # Memory usage
&gt;&gt;&gt; sys.getsizeof(Decimal(num))
104

&gt;&gt;&gt; sys.getsizeof(float(num))
24


&gt;&gt;&gt; # Performance
&gt;&gt;&gt; %timeit float(num)
140 ns ± 2.27 ns per loop (mean ± std. dev. of 7 runs, 10000000 loops each)

&gt;&gt;&gt; %timeit Decimal(num)
192 ns ± 9.42 ns per loop (mean ± std. dev. of 7 runs, 1000000 loops each)
</code></pre>
In your particular case you can use @Mark Byers solution.

blocks|key|827841|text|有两种浮点数据类型。Float和Decimal。这取决于您的程序需求，您想要使用哪一个。Decimal提供了很高的精确度，而且比Float更精确。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|827842|要将值字符串转换为浮点型，只需执行以下操作：|827843|num+=+"29.0"
print+(float(num))|code-block|syntax|javascript|827844|将字符串转换为小数的步骤|827845|from+decimal+import+Decimal
num+=+"29.0"
print+(Decimal(num))|827846|对于您的特定问题，您可以使用以下代码。这两个都为我工作。|827847|from+decimal+import+Decimal
import+re

result+=+[float(x.strip('+"'))+for+x+in+A1]
print(result)
#[29.0,+65.2,+75.2]


result+=+[Decimal(x.strip('+"'))+for+x+in+A1]
print(result)
#[Decimal('29.0'),+Decimal('65.2'),+Decimal('75.2')]


result+=+[float(re.search(r'\d%2B.\d%2B',number).group())+for+number+in+A1]
print(result)
#[29.0,+65.2,+75.2]

result+=+[Decimal(re.search(r'\d%2B.\d%2B',number).group())+for+number+in+A1]
print(result)
#[Decimal('29.0'),+Decimal('65.2'),+Decimal('75.2')]|827848|entityMap^0|A|5|G|7|18|7|1S|5|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@$9|X|A|Y|B|C]|$9|Z|A|10|B|C]|$9|11|A|12|B|C]|$9|13|A|14|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|15|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|16|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|17|8|@]|D|@]|E|$]]|$1|O|3|P|5|J|7|18|8|@]|D|@]|E|$K|L]]|$1|Q|3|R|5|6|7|19|8|@]|D|@]|E|$]]|$1|S|3|T|5|J|7|1A|8|@]|D|@]|E|$K|L]]|$1|U|3|-4|5|6|7|1B|8|@]|D|@]|E|$]]]|V|$]]

There are two floating-point data types. <code>Float</code> and <code>Decimal</code>. It depends on your program demand which one you want to use. <code>Decimal</code> provides a high level of accuracy and it's more precise than <code>Float</code>.
To convert a value string to float just do it:
<pre><code>num = &quot;29.0&quot;
print (float(num))
</code></pre>
To convert string to decimal
<pre><code>from decimal import Decimal
num = &quot;29.0&quot;
print (Decimal(num))
</code></pre>
For your specific question, you can use the below code. Both are working for me.
<pre><code>from decimal import Decimal
import re

result = [float(x.strip(' &quot;')) for x in A1]
print(result)
#[29.0, 65.2, 75.2]


result = [Decimal(x.strip(' &quot;')) for x in A1]
print(result)
#[Decimal('29.0'), Decimal('65.2'), Decimal('75.2')]


result = [float(re.search(r'\d+.\d+',number).group()) for number in A1]
print(result)
#[29.0, 65.2, 75.2]

result = [Decimal(re.search(r'\d+.\d+',number).group()) for number in A1]
print(result)
#[Decimal('29.0'), Decimal('65.2'), Decimal('75.2')]
</code></pre>

I have a python list with strings in this format:

<pre><code>A1 = [' "29.0" ',' "65.2" ',' "75.2" ']
</code></pre>

How do I convert those strings into decimal numbers to perform arithmetic operations on the list elements?

Python: Converting string into decimal number

Python

我有一个python列表，其中包含以下格式的字符串：A1 = [' "29.0" ',' "65.2" ',' "75.2" ']如何将这些字符串转换为十进制数，以便对列表元素执行算术运算？

问Python:将字符串转换为十进制数
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