This question already has answers here:
Print pi to a number of decimal places
(8 answers)
Closed 2 years ago.
I am trying to get pi value in python. Here is my source code.
import math
pi_formatted_float = "{:.5000f}".format(math.pi)
print(pi_formatted_float)
Using the source code I only can get 48 decimal places. Others are only 00000000....
More simply, you can test with
>>> "{:.60f}".format(1/3)
'0.333333333333333314829616256247390992939472198486328125000000'
It's not just a problem of PI, but common in all float type. You may find more information from Limiting floats to two decimal points.
Related
This question already has answers here:
Why does changing the sum order returns a different result?
(7 answers)
Is floating point math broken?
(31 answers)
Closed 2 years ago.
I am working on some floating point addition in Python, i found this difference, changing the order of addition changes the value.
v1=2.7776548790102065
v2=2.932026860135167
v3=-2.5635999386901154
v4=-5.884153623433478
v5=0.16152830205880864
v6=2.614447767673556
v7=5.651999753771971
v8=-7.074990233473147
v9=12.624973219138516
print(v1+v2+v3+v4+v5+v6+v7+v8+v9) # 11.239886986191486
print(v1+v4+v7+v2+v5+v8+v3+v6+v9) # 11.239886986191484
can anyhow suggest me how to rectify this?
This question already has answers here:
Is floating point math broken?
(31 answers)
Closed 5 years ago.
https://i.imgur.com/YYNhvNv.png
Its adding in 1 at the end of that console log output. Why?
Answer is suppose to be only 13.37
Likely because it is adding to numbers of type double (I am not a huge Python expert though, so I could be wrong). The doubletype, much like single does not have perfect precission. Hence some decimal errors can occur...
This question already has answers here:
Is floating point math broken?
(31 answers)
Closed 7 years ago.
When I divide 1/5e-5 it gives the correct answer but 1/5e-6 gives an answer close to the correct one.
>>> 1/5e-5
20000.0
>>> 1/5e-6
199999.99999999997 (should be 200000)
>>>
How can I get it to show the exact value. I tried importing decimel, numpy and scipy but none of them change the result.
You can get decimal to do this properly -- You just have to avoid using floating point numbers along the way:
>>> import decimal
>>> decimal.Decimal('1') / (decimal.Decimal('5') / decimal.Decimal('1000000'))
Decimal('2E+5')
This question already has answers here:
What do numbers starting with 0 mean in python?
(9 answers)
Closed 7 years ago.
I was playing around with Python. I had a doubt about the power operation in Python. So, I tried this:
0726**13 = 54609997061205831773270000000000000L
726**13 = 15565965698792536237226936270158258176L
Why is there a difference between these two? I know it might be trivial. But, I could not figure it out. Could someone please explain? Thanks.
It's because an integer constant beginning with 0 is taken to be an octal value. In this case, 0726 is interpreted as 470:
>>> 0726
470
>>> 470**13
54609997061205831773270000000000000L
>>>
Numbers starting with 0 in Python are represented in Base 8 (octal numbers). That's why you're getting different results.
This question already has answers here:
What do numbers starting with 0 mean in python?
(9 answers)
Closed 7 years ago.
I am trying to solve a problem using python. In which I have to deal with large integers (upto 500 digits). According to my current stage of understanding, python can handle any numbers in same traditional way. But I have problem in simple addition like this:
>>> p= 1001101111101011011100101100100110111011111011000100111100111110111101011011011100111001100011111010
>>> q= 0011111011111010111101111110101101111001111111100011111101101100100011010011111011111110110011111000
>>> p+q
1001101111105557844987142979708366943425581971579987152809865568761000527613931421735161949470823522L
Can anyone please explain why i got such an error.
Var q starts with a zero, making it an octal number, rather than decimal