6

How do I convert a scientific notation to floating point number? Here is an example of what I want to avoid:

Python 2.7.3 (default, Apr 14 2012, 08:58:41) [GCC] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> a=[78.40816326530613, 245068094.16326532]
>>> print a[0]/a[1]
3.19944395589e-07
>>> print float(a[0]/a[1])
3.19944395589e-07
>>> print float(a[0])/float(a[1])
3.19944395589e-07
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3 回答 3

11

Use string formatting:

>>> "{:.50f}".format(float(a[0]/a[1]))
'0.00000031994439558937568872208504280885144055446290'
于 2013-06-06T12:49:45.150 回答
9

The scientific notation is just a convenient way of printing a floating point number. When there are a lot of leading zeros as in your example, the scientific notation might be easier to read.

In order to print a specific number of digits after a decimal point, you can specify a format string with print:

print 'Number is: %.8f' % (float(a[0]/a[1]))

Or you can use format() as in the other answers.

于 2013-06-06T12:51:57.733 回答
4

That is already a floating point number, it just prints in a friendly format. If you want to show a certain amount of decimal places when printing, use format:

>>> print format(a[0]/a[1], '.65f')
0.00000031994439558937568872208504280885144055446289712563157081604
于 2013-06-06T12:50:28.433 回答