Introduction to Python Programming Course - Part 3

Getting some momentum going! And not that many more parts to this types and operations bit of the course. Last time it was all about Ints, Floats, Bools and Strings - different types and ways of using different operators with them. 

Start Time - unknown

22. String Methods Practice

\n - special way of putting in a line break. 

OK learned some new methods!

verse_length = len(verse)

print(verse_length)

print(verse.find("and"))

print(verse.index("and"))

print(verse.rfind("you"))

print(verse.count("you"))


So find and index - at what character index does 'and' first appear; rfind - last appear for "you" and count is of a specific string within a string "you". Had to look them up but that's good - that was the point of this challenge!

One thing I didn't do was the descriptive message. For that it is using the 'format' function. 

Use of {} for the missing values. Let's just practice that...

This is what they did - 

message = "Verse has a length of {} characters.\nThe first occurence of the \

word 'and' occurs at the {}th index.\nThe last occurence of the word 'you' \

occurs at the {}th index.\nThe word 'you' occurs {} times in the verse."


length = len(verse)

first_idx = verse.find('and')

last_idx = verse.rfind('you')

count = verse.count('you')

print(message.format(length, first_idx, last_idx, count))


Something to get used to is using {}, then doing a specific sequence so that they match up. Interesting!

Paused after approx. 20 minutes


Continued next day 

23. Solution

All good


24. There's a bug in my code

Errors - 

Division by zero (seen this one already)

Syntax - parsing EOF - something missing like closing parentheses or ending quotes

Type error - len - could be used for many functions - not the right number or arguments given

There are other ones too


A top tip is to search for the error message on google. Also print statements - these then tell you if there is an error or not.


26. Summary

SO, what we have learned in this section of the course..

Data types - int, float, string and bool

Operators - four main types plus exponentiation, modulo, integer division

Assignment - = but also += etc

Comparisons - < > != etc

Logical - keywords of or, and not


There was more - not in the summary. 

Use of strings and performing functions e.g. len for length. Combining values e.g. strings together. 

Use of _ for separating words, various other functions with strings. Use of the {} in a value, then putting in the values after. Then as long as number of arguments match, it will work!


Finished after approx. 20 minutes.

Total time - 40 minutes

Enough for now. Will do a bit more at the weekend, which will be 'Concepts'. This will be going in deeper but I'm confident I'll keep developing.

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