read_csv( 'large.csv', chunksize=chunksize, dtype=dtype_map ) # # 然后每个chunk进行一些压缩内存的操作,比如全都转成sparse类型 # string类型比如,学历,可以转化成sparse的category变量,可以省很多内存 sdf = pd.concat( chunk.to_sparse(fill_value=0.0) for chunk in chunks ) #很稀疏有可能可以装的下...
# multiple.sequences.explicit.pypeople = ['Conrad','Deepak'
这里还有一些例子: >>># 3 into integer myint>>>myint =3>>># a string of characters into a string variable>>>text ='Some text'>>># a floating point number>>>cost =3*123.45>>># a longer string>>>Name ='Mr'+' '+'Fred'+' '+'Bloggs'>>># a list>>>shoppingList = ['ham',...
print("Matched line in "+ file_path +": "+ line.strip()) # Append the tuple (collapse_ratio, tile_name, pre_count, post_count, deleted_count, file_path) to the matched_lines list matched_lines.append((collapse_ratio, tile_name, pre_count, post_count, deleted_count, file_path)) ...
find string.find(sub, start=0, end=len(string)) string:要进行查找操作的原始字符串。 sub:必需参数,是要查找的子字符串。start:可选参数,指定开始查找的起始索引位置,默认值为 0,表示从字符串的开头开始查找。 end:可选参数,指定查找的结束索引位置,默认值为字符串的长度,表示查找至字符串的末尾。查找范围...
Shells typically do their own tokenization, which is why you just write the commands as one long string on the command line. With the Python subprocess module, though, you have to break up the command into tokens manually. For instance, executable names, flags, and arguments will each be ...
You can use single and double quotes for a single line of characters. Multiple lines are generally put in triple quotes.String common methodsGet the index of a substring in a string. # find the index of a "c" in a string "abcde" >>> "abcde".index("c") 2...
Keep Learning Related Topics:basicsbest-practices Recommended Video Course:Replacing a String in Python Related Tutorials: Getters and Setters: Manage Attributes in Python How to Use sorted() and .sort() in Python How to Split a Python List or Iterable Into Chunks ...
>>> myvar, mystring = mystring, myvar 数据类型 Python具有列表(list)、元组(tuple)和字典(dictionaries)三种基本的数据结构,而集合(sets)则包含在集合库中(但从Python2.5版本开始正式成为Python内建类型)。列表的特点跟一维数组类似(当然你也可以创建类似多维数组的“列表的列表”),字典则是具有关联关系的数组(...
The loop checks if the user entersexit(regardless of the case, as we uselower()for case-insensitive comparison). Ifexitis detected, the loop terminates withbreak. Each line entered by the user is appended to theuser_inputstring, followed by a newline character to preserve the line structure...