...Python中我只讲两个函数: melt #数据宽转长 pivot_table #数据长转宽 Python中的Pandas包提供了与R语言中reshape2包内几乎同名的melt函数来对数据进行塑型...除此之外,我了解到还可以通过stack、wide_to_long函数来进行宽转长,但是个人觉得melt函数比较直观一些,也与R语言中的数据宽转长用法一致,推荐...
现在如果列中包含了交叉类别,比如期中期末的类别和语文数学的类别,那么想要把 values_name 对应的 Grade 扩充为两列分别对应语文分数和数学分数,只把期中期末的信息压缩,这种需求下就要使用 wide_to_long 函数来完成。 df = pd.DataFrame({'Class':[1,2],'Name':['San Zhang','Si Li'],'Chinese_Mid':[8...
There are a number of basic operations for rearanging tabular data. These are alternatingly referred to asreshape or pivotoperations. 多层索引重塑 Hierarchical indexing provides a consistent way to rearrange data in a DataFrame. There are two primary actions: stack - 列拉长index This "rotates...
方法描述DataFrame.apply(func[, axis, broadcast, …])应用函数DataFrame.applymap(func)Apply a function to a DataFrame that is intended to operate elementwise, i.e.DataFrame.aggregate(func[, axis])Aggregate using callable, string, dict, or list of string/callablesDataFrame.transform(func, *args,...
melt() Reshape the DataFrame from a wide table to a long table memory_usage() Returns the memory usage of each column merge() Merge DataFrame objects min() Returns the min of the values in the specified axis mod() Modules (find the remainder) of the values of a DataFrame mode() Return...
inplace=False,默认该删除操作不改变原数据,而是返回一个执行删除操作后的新dataframe; inplace=True,则会直接在原数据上进行删除操作,删除后无法返回。 因此,删除行列有两种方式: 1)labels=None,axis=0 的组合 2)index或columns直接指定要删除的行或列 ...
Help on function melt in module pandas.core.reshape.melt:melt(frame: 'DataFrame', id_vars=None, value_vars=None, var_name=None, value_name='value', col_level=None, ignore_index: 'bool' = True) -> 'DataFrame'Unpivot a DataFrame from wide to long format, optionally leaving identifiers ...
But for DataFrame, we will need a two dimensional array. To create a two dimensional array, we have two different approaches: Using the arange() and reshape(): We can use both these methods one after another to generate a range of values and place them in a proper shape. Here is a ...
Flexible and powerful data analysis / manipulation library for Python, providing labeled data structures similar to R data.frame objects, statistical functions, and much more - pandas/pandas/core/reshape/melt.py at v0.24.1 · pandas-dev/pandas
DataFrame.eq(other[, axis, level]) #类似Array.eq DataFrame.combine(other,func[,fill_value, …]) #Add two DataFrame objects and do not propagate NaN values, so if for a DataFrame.combine_first(other) #Combine two DataFrame objects and default to non-null values in frame calling the method...