I thought it was probably an important concept to get to know Python I would like to describe and share ^ ^ A description of the built-in object.
There is an idea.
Sequences literally represent serial numbers. The map is "photo-like" in my own words, To put it a little more, it refers to something that cannot be separated (it becomes meaningless if separated).
Python strings and lists are sequences.
In other words, you can do the following:
String 【result】 print u'Pillow soup' [2: 4] And others
However, it cannot be used in the following ways. × str = 'testing' str[0] = 'a' Because it is an immutable object.
list 【result】 print [1, 2, 3, 4, 5, 6][5] 6
Since it is a serial number, you can slice it in a sequence. Since this is a mutable object, you can perform the following operations. array = [1, 2, 3, 4, 5, 6] array[0] = 8 print array [8, 2, 3, 4, 5, 6]
for, The Python dictionary type is a map.
It is a key-value, a hash in Perl etc. I think it corresponds to the associative array of PHP.
heights = {"john":182, "mike":173, "kevinn":190, "George":181, "Randy":184} print heights["Randy"] 184
You can use it like this.
However, it cannot be taken out sequentially. × print heights["john":"kevinn"]
However, because it is variable, you can change or add elements. heights ["mike"] = 175 # 2cm stretched!
Today is this strange ^^