Python print float numbers

How to suppress scientific notation when printing float values?

My quotient displays as 1.00000e-05 . Is there any way to suppress scientific notation and make it display as 0.00001 ? I’m going to use the result as a string.

It is disappointing that none of the answers here address the question. It would be nice if there was a way to prevent python(3) from using scientific notation at all except when specified explicitly. All of the answers require the user to explicitly suppress scientific notation, which is not the same as generally suppressing the implicit use of scientific notation from within python.

Not worth an answer on it’s own, but I believe stackoverflow.com/questions/67879685/… is better than any existing answer here if combined with .replace(«,», «») .

Python is so insane, I cannot stop being amazed by its intrinsic stupidity and lack of practicality comparing to literally any other modern language. Such a bummer this abomination became so popular.

16 Answers 16

Using the newer version ».format (also remember to specify how many digit after the . you wish to display, this depends on how small is the floating number). See this example:

>>> a = -7.1855143557448603e-17 >>> ''.format(a) '-0.000000' 

as shown above, default is 6 digits! This is not helpful for our case example, so instead we could use something like this:

>>> ''.format(a) '-0.00000000000000007186' 

Update

Starting in Python 3.6, this can be simplified with the new formatted string literal, as follows:

I guess by using a variable, give it the desired number of digits, and use it instead of the literal number e.g. f»«It does not work for me time.time() #shortStuff end = time.time() print( ‘<:.20>‘.format(end — start),»sec»)

but you need to manage precision yourself. e.g.,

I suggest clarifying your statement to say, «you manage the display of precision yourself.» The actual (Python internal) precision isn’t changed, as is often done in other languages.

With newer versions of Python (2.6 and later), you can use ».format() to accomplish what @SilentGhost suggested:

Another option, if you are using pandas and would like to suppress scientific notation for all floats, is to adjust the pandas options.

import pandas as pd pd.options.display.float_format = ''.format 

I found this answer useful specially combining it with the other answer here for further endorsement: import pandas as pd import numpy as np pd.options.display.float_format = ».format np.set_printoptions(suppress=True)

Most of the answers above require you to specify precision. But what if you want to display floats like this, with no unnecessary zeros:

1 0.1 0.01 0.001 0.0001 0.00001 0.000001 0.000000000001 

import numpy as np def format_float(num): return np.format_float_positional(num, trim='-') 

this is the best answer if you want a general number of decimal places (ie. do not need to specify decimal places before).

In case of numpy arrays you can suppress with suppress command as

import numpy as np np.set_printoptions(suppress=True) 

You can use the built-in format function.

>>> a = -3.42142141234123e-15 >>> format(a, 'f') '-0.000000' >>> format(a, '.50f') # Or you can specify precision '-0.00000000000000342142141234122994048466990874926279' 

Unfortunately this adds garbage numbers at the end of nice round floats like: format(0.001, ‘.50f’) = ‘0.00100000000000000002081668171172168513294309377670’

This will work for any exponent:

def getExpandedScientificNotation(flt): str_vals = str(flt).split('e') coef = float(str_vals[0]) exp = int(str_vals[1]) return_val = '' if int(exp) > 0: return_val += str(coef).replace('.', '') return_val += ''.join(['0' for _ in range(0, abs(exp - len(str(coef).split('.')[1])))]) elif int(exp) < 0: return_val += '0.' return_val += ''.join(['0' for _ in range(0, abs(exp) - 1)]) return_val += str(coef).replace('.', '') return return_val 

This is using Captain Cucumber's answer, but with 2 additions.

1) allowing the function to get non scientific notation numbers and just return them as is (so you can throw a lot of input that some of the numbers are 0.00003123 vs 3.123e-05 and still have function work.

2) added support for negative numbers. (in original function, a negative number would end up like 0.0000-108904 from -1.08904e-05)

def getExpandedScientificNotation(flt): was_neg = False if not ("e" in flt): return flt if flt.startswith('-'): flt = flt[1:] was_neg = True str_vals = str(flt).split('e') coef = float(str_vals[0]) exp = int(str_vals[1]) return_val = '' if int(exp) > 0: return_val += str(coef).replace('.', '') return_val += ''.join(['0' for _ in range(0, abs(exp - len(str(coef).split('.')[1])))]) elif int(exp) < 0: return_val += '0.' return_val += ''.join(['0' for _ in range(0, abs(exp) - 1)]) return_val += str(coef).replace('.', '') if was_neg: return_val='-'+return_val return return_val 

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How To Print Float Values in Python

Python supports not only integers but also floating-point numbers . Many new developers don’t know how to print float values in Python. In this article, we will share with you different ways to get this work done! Scroll down to read!

How to print float values in Python

Below is how to print float values in Python.

Add the floating point number in print() function directly

You use the print() function to print the float values to the screen. This function takes parameters of different data types, including string , integer , list , floating point number , and so on.

print([floating point number])

You add the float values into the print() function directly. Don’t put the float in between the "" or else the values will be in string format.

# Print the float values: 28.12 print(28.12)

Assign the float value to a variable and put this variable in print() function

You can create a variable and assign float values to it. And then use the variable as the parameter for the print() function. The print() will show the float value on the screen.

[variable] = [floating point number] print([variable])

Remember to put the variable directly inside the () of the print() function. Don’t place it between "" or else the function will just print out the variable name in string format.

# Assign the float value 28.12 to the variable fltNumber fltNumber = 28.12 # Print the float values: 28.12 print(fltNumber)

Print the float value of an integer number

Python has a built-in function, which is known as float() . This function allows the developers to force the type of any number to the float format.

For example, you have an integer number, which is 2. The float() function will convert this number to 2.0.

[variable] = [int] [variable] = float([variable]) print([variable])

You assign the integer value to a variable. And then use the variable as the parameter for the float() function. It will turn the number into a floating-point number format. This time, if you print the variable, the output will show a float value.

# Assign the int value: 28 to the variable: number number = 28 print(number) print("Type of number: ", type(number)) # Convert the int to float values number = float(number) # Print the float values: 28.0 print(number) print("Type of number after changed: ", type(number))

28 Type of number: 28.0 Type of number after changed:

Of course, you can convert an int to a float directly, using the following syntax:

The int number will be converted to float before it is printed out to the screen.

# Convert the int: 28 to float value and print it out print(float(28))

Summary

To summarize, we have shown how to print float values in Python. You can print the float directly or print a variable that has the float value assigned. On the other hand, you can take advantage of the float() function to convert int value to float value.

I am William Nguyen and currently work as a software developer. I am highly interested in programming, especially in Python, C++, Html, Css, and Javascript. I’ve worked on numerous software development projects throughout the years. I am eager to share my knowledge with others that enjoy programming!

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Python print 2 decimal places [%.2f in Python]

In this Python tutorial, we will discuss on how to print 2 decimal places in Python.

• Python print 2 decimal places
• Python float precision truncate
• Python float precision ceil
• Python float precision floor
• Python decimal format
• Python round numbers
• Limiting floats to two decimal points

Python print 2 decimal places

In Python, to print 2 decimal places we will use str.format() with “” as string and float as a number. Call print and it will print the float with 2 decimal places.

float = 2.154327 format_float = "".format(float) print(format_float)

After writing the above code (python print 2 decimal places), Ones you will print “ format_float ” then the output will appear as a “ 2.15 ”. Here, it will format the float with 2 decimal places.

You can refer to the below screenshot python print 2 decimal places.

Python float precision truncate

Firstly, we need to import math module. Then the trunc() function is used to remove all decimal parts from the floating-point numbers and it returns only the integer part of the number.

import math float = 12.16785 print("The value of number is: ",end="") print (math.trunc(float))

After writing the above code (python float precision truncate), Ones you will print “ math.trunc(float)” then the output will appear as a “ The value of a number is: 12 ”. Here, trunc() will print integer value after truncating.

You can refer to the below screenshot for python float precision truncate

Python float precision ceil

In Python, the ceil() function is used to return the ceiling value of a number. The ceil value is the smallest integer greater than the number.

import math float = 12.16785 print("The smallest integer greater than number is: ",end="") print (math.ceil(float))

After writing the above code (python float precision ceil), Ones you will print “ math.ceil(float) ” then the output will appear as a “ The smallest integer greater than a number is: 13 ”. Here, we used ceil to print numbers after the ceiling. It will return the smallest integer greater than the given number.

You can refer to the below screenshot for python float precision ceil.

Python float precision floor

Python floor() function is used to return the floor value of a number. The floor value is the greatest integer smaller than the number.

import math float = 12.16785 print("The greatest integer smaller than number is: ",end="") print (math.floor(float))

After writing the above code (python float precision floor), Ones you will print “math.floor(float)” then the output will appear as a “ The greatest integer smaller than a number is: 12 ”. Here, we used the floor to print numbers after flooring. It will return the greatest integer smaller than the number.

You can refer to the below screenshot for python float precision floor.

Python decimal format

To format decimals, we will use str.format(number) where a string is ‘’ and it will format string with a number. Also, it will display the number with 1 number before the decimal and up to 2 numbers after the decimal.

number = 1.345 f = ''.format(number) print(f)

After writing the above code (python decimal format), Ones you will print “ f ” then the output will appear as a “ 1.34 ”. Here, formatting decimals displays numbers with a certain number after the decimal point.

You can refer to the below screenshot for python decimal format.

Python round numbers

To round numbers in python, we will use the round() function. The round function will round off a number to a given number of digits and makes rounding of numbers easier.

number = 1.345 print(round(number))

After writing the above code (python round numbers), Ones you will print “ number ” then the output will appear as a “ 1 ”. Here, the number 1.345 float number will be rounded to 1.

You can refer to the below screenshot for python round numbers.

Limiting floats to two decimal points

The round() function returns a floating-point number which will be rounded to specified numbers, and it will round the float to two decimal places.

my_float = 2.13456 limit_float = round(my_float, 2) print(limit_float)

After writing the above code (limiting floats to two decimal points), Ones you will print “limit_float” then the output will appear as a “ 2.13 ”. Here, the round(number) with a float number and 2 as ndigits to round float to two decimal points.

You can refer to the below screenshot for python round numbers.

You may like the following Python tutorials:

In this tutorial, we learned how to print 2 decimal places in python and also we covered the below topics:

• Python print 2 decimal places
• Python float precision truncate
• Python float precision ceil
• Python float precision floor
• Python decimal format
• Python round numbers
• Limiting floats to two decimal points

I am Bijay Kumar, a Microsoft MVP in SharePoint. Apart from SharePoint, I started working on Python, Machine learning, and artificial intelligence for the last 5 years. During this time I got expertise in various Python libraries also like Tkinter, Pandas, NumPy, Turtle, Django, Matplotlib, Tensorflow, Scipy, Scikit-Learn, etc… for various clients in the United States, Canada, the United Kingdom, Australia, New Zealand, etc. Check out my profile.

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