Python 9b - Number Handling

Rounding Numbers

The round() command is used to round a value to a certain number of decimal places.

Type your variable into the round command brackets, add a comma and state the number of decimal places to round to.

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If you type only the variable, it will round the number to the nearest whole value.

Practice Task 1

Ask the user to enter any large number.

Ask the user to enter another large number.

Divide the two numbers and print the answer to 3 decimal places.

Example solution:

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Using Numbers as Strings

The following techniques all require the integer to be converted into a string first using the str command.

Just like a string, you can shorten a variable to only display a certain length.

 

Remember that Python starts at zero.

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You can select a specific digit in the same manner as when selecting characters in a string.

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If you want to use your variable as an integer again later you would need to convert it from a string to an integer using the int command.

Again, reversing a number is the same as reversing a string.

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You can also use other string handling methods such as .startswith() or .endswith()

Practice Task 2

Ask the user to enter a 10 digit number.

Select the 2nd and 8th digits and add them together.

Print the total.

Example solution:

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