Table of Contents

**Summary: **Use the string literal syntax `f"{number:.nf}"`

to suppress the scientific notation of a number to its floating-point representation.

**Problem Formulation: ** How will you suppress a number represented in scientific notation by default to a floating-point value?

**Note: **Generally, Python represents huge floating-point numbers or very small floating-point numbers in their scientific form. Scientific notation of a number represents the number in terms of powers of 10. For example, the scientific notation for the number `0.0000025`

is `2.5e-6`

.

**Example: **Consider the following code snippet.

number = 2.5 / 1000000 print(number)

The output is `2.5e-06`

. How will you suppress the scientific notation and display the output as `0.000025`

?

## 🎥**Video Walkthrough**

**Solution 1: Using String Literal (f-string)**

✨**Approach: **If you are using Python 3.6 or above, then the simplest solution to our problem is to use the string literal syntax `f"{number:.nf}"`

to represent the given floating-point number in its decimal format with `n`

places of decimal points.

**Code:**

number = 2.5 / 1000000 print(f"Scientific Notation: {number}") print(f"Decimal Representation: {number:.7f}")

**Output:**

Scientific Notation: 2.5e-06 Decimal Representation: 0.0000025

**TRIVIA: **The string literal technique relies upon `str.format()`

implicitly.

**Solution 2: Using str.format()**

`format()`

is a built-in function in Python that returns a formatted string. It formats the specific values and inserts them in the placeholder of the string.

✨**Approach: **To represent the scientific notation of the output in decimal format with `n`

places following the decimal point, use `str.format(number)`

where `str`

is “`{:.nf}`

” .

**Code:**

number = 2.5 / 1000000 print("Scientific Notation: ", number) print("Decimal Representation: {:.7f}".format(number))

**Output:**

Scientific Notation: 2.5e-06 Decimal Representation: 0.0000025

**Note: **Ensure that you manage the value of `n`

, that is, the number after the decimal points you want to display properly, depending on how small the floating-point number is. For example, have a look at the following example:

a = -7.1855143557448603e-17 print('{:f}'.format(a)) # -0.000000

Since the default number of digits after the decimal point is 6, the output of the above snippet will be `-0.000000`

. This is not helpful for the given example. Hence, we could use something which looks like this:

a = -7.1855143557448603e-17 print('{:.30f}'.format(a)) # OUTPUT: -0.000000000000000071855143557449

**Recommended Tutorials** to understand how string formatting works in Python:

**Solution 3: Using % Formatting**

The % operator allows you to format a string object in Python. Conversion specifiers, like `%f`

and` %s`

, are used in the format string as placeholders. These specifiers dictate how % will format the values.

✨**Approach: **If you are using an older version of Python, use `%.nf`

to suppress the scientific notation to a floating-point value upto `n`

decimal places. Remember to manage the precision manually.

**Code:**

number = 2.5 / 1000000 print("Scientific Notation: ", number) print("Decimal Representation: %.7f" % number)

**Output**:

Scientific Notation: 2.5e-06 Decimal Representation: 0.0000025

**Solution 4: Using Pandas**

✨**Approach: **Another option, if you are using pandas and would like to suppress scientific notation for all floats, is to adjust Pandas options as shown below.

**Code:**

import pandas as pd pd.options.display.float_format = '{:.10f}'.format df = pd.DataFrame([1.192433e-06, 1.293066e-06, 1.077142e-06], index=['foo', 'bar', 'baz'], columns=['time']) print(df)

**Output:**

time foo 0.0000011924 bar 0.0000012931 baz 0.0000010771

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**Solution 5: Using Numpy**

In the above approaches, we had to specify the precision manually. But, what if you do not have an idea about the precision? This is where the `Numpy`

library will help you.

✨**Approach: **`format_float_positional()`

is a function of the Numpy library in Python that formats a floating-point scalar. It then returns the decimal string representation of the floating-point value passed. The optional `trim`

argument, when set to `'-'`

trims trailing zeros and any trailing decimal point if not needed.

**Code:**

import numpy as np number = 2.5 / 1000000 print("Scientific Notation: ", number) print("Decimal Representation: ", np.format_float_positional(number, trim='-'))

**Output:**

Scientific Notation: 2.5e-06 Decimal Representation: 0.0000025

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**Solution 6: **Using decimal Module

Another workaround to the given problem is to import the decimal module and use its Decimal instance, as shown below.

from decimal import Decimal number = str(Decimal(2.5) / Decimal(1000000)) print(number)

**Output:**

0.0000025

⚠️**Caution: **This approach won’t work for values smaller than `1e-6`

. It turns values lesser than `1e-6`

to their scientific notation.

**Frequently Asked Questions (Related)**

### ✨**How to Print a Number in Scientific Notation in Python?**

You can convert a number to its scientific notation using `"{:e}".format(num)`

. To specify the precision, i.e., the number of digits after the decimal point, use `"{:.Ne}"`

, where `N`

represents the number of digits.

**Example:**

num = 1250000000 # format number into scientific notation print("{:e}".format(num)) # format scientific notation with 2 digits print("{:.2e}".format(num))

**Output:**

1.250000e+09 1.25e+09

### ✨**How to Limit Floats to Two Decimal Points in Python?**

Use the built-in function `round()`

to round off the given decimal number to the given precision.

**Example:**

x = 3.14667 y = round(x) z = round(x, 3) # Limit the float value to three decimal points print("x=", x) print("y=", y) print("z=", z)

**Output:**

x= 3.14667 y= 3 z= 3.147

**Read Here: How to Limit Floats to Two Decimal Points in Python?**

### ✨**How to Match Scientific Notation in a String? **

Leverage the power of regex to detect the presence of numbers represented in their scientific notation in a given string.

**Example:**

import re val = "the scientific notation for the number 0.0000025 is 2.5e-6" num = re.compile('[-+]?[\d]+\.?[\d]*[Ee](?:[-+]?[\d]+)?') print(re.findall(num, val))

**Output:**

['2.5e-6']

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**Conclusion**

To wrap things up, if you are on a newer version of Python, then it is advisable to use the string literal approach to suppress the scientific notation to a floating-point value. In case you are dealing with a Pandas dataframe or a Numpy array, then proposed solutions 4 and 5 are worth the try.

With that, we come to the end of this tutorial. Please **subscribe** and stay tuned for more interesting tutorials in the future. Happy learning!