Data Frames

Date:2012-09-28 (last modified), 2006-09-13 (created)

NOTE: this entry is outdated. You will likely want to use pandas instead.

The class, posted by Andrew Straw on the) scipy-user mailing list original link, is an extremely useful tool for using alphanumerical tabular data, as often found in databases. Some data which might be ingested into a data frame could be: || ID || LOCATION || VAL_1 || VAL_2 || || 01 || Somewhere || 0.1 || 0.6 || || 02 || Somewhere Else || 0.2 || 0.5 || || 03 || Elsewhere || 0.3 || 0.4 ||

The class can be populated from data from a CSV file (comman-separated values). In its current implementation, these files are read with Python's own CSV module, which allows for a great deal of customisation.

Example Usage

A sample file CSV file from Access2000 is in CSVSample.csv We first import the module:

In [ ]:
import DataFrame

and read the file in using our desired CVS dialect:

In [ ]:
df = DataFrame.read_csv("CSVSample.csv",dialect=DataFrame.access2000)

(note that the dialect is actually defined in the DataFrame class). It is often useful to filter the data according to some criterion.

Compatibility with Python 2.6 and above

Starting with Python 2.6, the sets module is deprecated, in order to get rid of the warning, replace

In [ ]:
imports sets


In [ ]:
except NameError:
    from sets import Set as set

Section author: Unknown[8], Unknown[43], Unknown[44], Unknown[45]