4.4. String Operations¶
Strings are sequences of letters, numbers, punctuation, and spaces. Strings are defined at the Python REPL by enclosing letters, numbers, punctuation, and spaces in single quotes ' ' or double quotes " ".
>>> word = "Solution"
>>> another_word = "another solution"
>>> third_word = "3rd solution!"
In Python, string operations include concatenation (combining strings), logical comparisons (comparing strings) and indexing (pulling specific characters out of strings).
4.4.1. String Concatenation¶
Strings can be concatenated or combined using the + operator.
>>> word = "Solution"
>>> another_word = "another solution"
>>> third_word = "3rd solution!"
>>> all_words = word+another_word+third_word
>>> all_words
'Solutionanother solution3rd solution!'
To include spaces in the concatenated string, add a string which just contains one space " " in between each string you combine.
>>> word = "Solution"
>>> another_word = "another solution"
>>> third_word = "3rd solution!"
>>> all_words = word + " " + another_word + " " + third_word
>>> all_words
'Solution another solution 3rd solution!'
4.4.2. String Comparison¶
Strings can be compared using the comparison operator; the double equals sign ==. Note the comparison operator (double equals ==) is not the same as the assignment operator, a single equals sign =.
>>> name1 = 'Gabby'
>>> name2 = 'Gabby'
>>> name1 == name2
True
>>> name1 = 'Gabby'
>>> name2 = 'Maelle'
>>> name1 == name2
False
Capital letters and lower case letters are different characters in Python. A string with the same letters, but different capitalization are not equivalent.
>>> name1 = 'Maelle'
>>> name2 = 'maelle'
>>> name1 == name2
False