This question already has answers here:
Rounding a number in Python but keeping ending zeros
(6 answers)
Closed 6 years ago.
So let's say I have this code:
num = 1.29283
round(num, 2)
That rounds to 1.29, but if I do this:
num = 1.30293
round(num, 2)
That rounds to 1.3. I want to know if there is a way to have it round to 1.30; I know it is the same number, but I need it to print 1.30.
You can use string formatting for this. A number in python does not have such a thing as trailing zeros. So your question only make sense for strings.
Example:
>>> num = 1.30293
>>> "{:.2f}".format(num)
'1.30'
The .2f says that this is a float (f) and that you want two digits after the point .2. Read more about string formatting here
Related
This question already has answers here:
How to display a float with two decimal places?
(13 answers)
Closed 3 years ago.
I want number from input to print out with 2 decimal places. You can assume that the number will always be a float.
num = 20.0
Desired output - 20.00.
I've tried this code:
num = round(num, 2)
num = float('{0.2f}'.format(num))
print(num)
This should work
print('{0.2f}'.format(num))
When you turn this string back into a float with float() the formatting is lost.
No matter what you do to the float value, as long as it is still a float, it does not have any internal concept of decimal places.
If you want to display two decimal places, then that happens when you convert to text - which everything you print is, whether you asked for the conversion or not. You cannot make num "be" 20.00 as opposed to 20.0, because those aren't actually different things. (And keep in mind that the float simply cannot represent all decimal values exactly.)
Therefore, we use string formatting in the print call:
num = 20.0
print('{.2f}'.format(num))
# Or, using f-strings:
print(f'{num:.2f}')
This question already has answers here:
Add zeros to a float after the decimal point in Python
(5 answers)
Closed 5 years ago.
I need to print some results with 5 numbers after decimal points. I'm using round() function but it doesn't output the last digit if it's a zero. Example:
print(str(round(-82.43670009888078, 5)))
print(str(round(49.5211007473081, 5)))
Would output:
-82.4367
49.5211
But I need:
-82.43670
49.52110
If the last digit isn't 0 it works fine.
You can use .format() to print decimals
print ("{:.5f}".format(a))
This will print >>> 49.52110 as desired.
OR
you could simply use
format(a, '.5f')
This question already has answers here:
Formatting floats without trailing zeros
(21 answers)
Closed 8 years ago.
I have written a code that will add up the values in a tuple and calculate the average:
def average(values):
return sum(values[0:]) / len(values[0:])
However, I get an unwanted floating point, like 2.0 instead of 2. How do I eliminate this, but still manage to get the correct average should the average not be an integer?
You may try like this:
if (yournumber).is_integer():
print int(n)
else
print (n)
This question already has answers here:
How to display a float with two decimal places?
(13 answers)
Pad python floats
(4 answers)
Closed 8 years ago.
I'm sorry, I know this must be a duplicate, I can't find where else it's posted. Please feel free to link me to the original question and mark this as duplicate.
I would like to print a 3 digits of a number AFTER the decimal point in it.
For example:
number = 523.637382
I would like to print: 523.637
I have a feeling I can use something similar to this
print(str(number)[:7])
>>>523.637
However, this will not work if the number before the decimal is not 3 decimals.
Bonus points:
Would this be easy?
number = 500.220
#magic
>>>500.22
number = 500.2000003
#magic
>>>500.2
A (built-in) function that could do this is round:
>>> number = 523.637382
>>> rounded = round(number, 3) # 3 decimal places, for example
>>> rounded
523.637
This has already been answered for example here.
The good news, to answer the second part of your question, is that the round function automatically removes trailing zeroes. It's much harder to retain the zeros if you're defining a new variable: you need the decimal module; but it looks that that isn't necessary here.
>>> number = 523.60000001
>>> rounded = round(number, 3)
>>> rounded
523.6
print("%.3f" % number)
or, using the new-style formatting,
print("{0:.3f}".format(number))
If you're printing a str like above you can use string interpolation:
number = 33.33333
print("{0:.3f}".format(number))
#=> 33.333
This question already has answers here:
How to truncate float values?
(31 answers)
Closed 9 years ago.
I've found dozen of answers, but non of them is what I'm looking for, I don't want to round up or down, I know that I can round numbers as follow:
>>> print('%.3f' % 15.555555)
15.556
>>> round(15.555555, 3)
15.666
But I need to get 15.555. Should I use regex?
Cheeky solution:
numstring = str(15.555555)
num = float(numstring[:numstring.find('.')+4])
My solution involving int abuse. int rounds towards the nearest 0. I multiply it by 10**3 to affect rounding. After using int, I divide it by 10**3 to get actual results.
It's safer, as it does work with e notation.
int(15.55555 * 10**3) / 10.0**3