我如何计算字符串中的浮点数，将浮点数识别为一个数字？ -Python

Question

I have a string of numbers separated by space like this

test_string = '2.02.02.02.02.02.02.02.0'

when I do len(lest_string), it returns 24, meaning it is counting the decimal point and decimal places. How do I count the elements in the string such that 2.0 is counted as 1 element and not 3 elements?

Answer 1

You can try this:

test_string = '2.02.02.02.02.02.02.02.0' 

print test_string.count("2.0")

Output:

8

If spaces are provided in the test_string:

test_string = '2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0'

print len(test_string.split())

Answer 2

If your numbers are actually separated by spaces you could do

test_string =  '2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0'
nums = [float(f) for f in test_string.split()]
how_many = len(nums)    # 8

Alternatively, if you are certain there is only ever exactly one space between numbers,

how_many = test_string.count(" ") + 1    # 8

or you could just

how_many = test_string.count(".")        # 8

Answer 3

In your test_string the numbers aren't separated by space. If they were, you could split() the test_string and get the length of the resulting list:

test_string = '2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0'
l = len(test_string.split())
print("Debug: l =", l)

Returns:

Debug: l = 8

Answer 4

test_string = '2.02.02.02.02.02.02.02.0'

or

test_string = '2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0'

count = len(re.findall(r'2.0', test_string))

output: 8