introduction to pandas data structure.pptx

introduction to pandas data structure.pptx

• 1.
  INTRODUCTION TO PANDASDATA STRUCTURE Nagendra Asstt. Professor B. N. College (University of Delhi)
• 2.
  Install Pandas Libraryin Jupyter
• 3.
  Series A series isa one dimensional array like object containing a sequence of values and an associate array of data labels, called its index.
• 4.
  Array representation andindex object of the Series via its value and index attributes
• 5.
  Creating a Serieswith an index identifying each data point with label
• 6.
  We can labelsin the index when selecting single values or a set of values
• 7.
  Using NumPy function,like filtering with a boolean array, scalar multiplication or applying math, will preserve the index-value link
• 8.
  A Series afixed-length , ordered dict, as it is a mapping of index values to data values
• 9.
  To check missingvalues
• 10.
  Series automatically alignsindex label in arithmetic operations
• 11.
  A Series indexcan be altered in-place by assignment
• 12.
  DataFrame A DataFrame representsa rectangular table of data and contains an ordered collection of columns, each of which can be a different value type. A DataFrame can easily constructed from dict of equal- length lists or NumPy arrays
• 13.
  The head methodselect only first five rows. Sequence of columns can be specified/arranged.
• 14.
  If we passa column that isn’t in the dict, it will appear with missing values in the result. A column in a DataFrame cab be retrieved as a Series either by dict-like notation or by attribute.
• 15.
  Rows can alsobe retrieved by position or name with the specific log attribute. Columns can be modified by assignment.
• 16.
  When assign listsor arrays to a column, the value’s length must match the length of the DataFrame. If we assign a Series, its label will be realigned exactly to DataFrame’s index, inserting missing values in any holes.
• 17.
  del method canbe used to remove this column. data is a nested dict of dicts Transpose the DataFrame with similar syntax to a NumPy array
• 18.
  The keys inthe inner dicts are combined and sorted to form the index in the result.
• 19.
  With Series, thevalues attribute returns to data combined in the DataFrame as a two-dimensional ndarray. Index objects are responsible for axis labels and other metadata.