Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.lang.python > #98728 > unrolled thread

Plotting timeseries from a csv file using matplotlib

Back to article view | Back to comp.lang.python

Contents

  Plotting timeseries from a csv file using matplotlib Karthik Sharma <karthik.sharma@gmail.com> - 2015-11-12 21:27 -0800
    Re: Plotting timeseries from a csv file using matplotlib Fabien <fabien.maussion@gmail.com> - 2015-11-13 12:51 +0100
    Re: Plotting timeseries from a csv file using matplotlib Denis McMahon <denismfmcmahon@gmail.com> - 2015-11-13 14:32 +0000

#98728 — Plotting timeseries from a csv file using matplotlib

I have some csv data in the following format.

Ln	Dr	Tag	 Lab	   0:01   0:02  0:03  0:04   0:05  0:06  0:07  0:08  0:09	
L0	St  	 vT	 4R	     0	       0	 0	  0	    0      0	     0	      0       0		
L2	Tx 	 st	 4R	     8	       8	 8	  8	    8	    8	     8	      8       8	
L2	Tx 	 ss	 4R	     1	       1	 9	  6	    1	    0	     0	      6       7	

I want to plot a timeseries graph using the columns (`Ln` , `Dr`, `Tg`,`Lab`) as the keys and the `0:0n ` field as values on a timeseries graph.I want all the timeseries to be plotted on a single timeseries? 

I have the following code.

    #!/usr/bin/env python

    import matplotlib.pyplot as plt 
    import datetime
    import numpy as np
    import csv 
    import sys 
    
    
    with open("test.csv", 'r', newline='') as fin:
        reader = csv.DictReader(fin)
        for row in reader:
              key = (row['Ln'], row['Dr'], row['Tg'],row['Lab'])
              #code to extract the values and plot a timeseries.                                                                                                                                                                             
    ~  

How do I extract all the values in columns `0:0n` without induviduall specifying each one of them. 
                            

[toc] | [next] | [standalone]

#98736

On 11/13/2015 06:27 AM, Karthik Sharma wrote:
> How do I extract all the values in columns

Have a look at pandas: 
http://pandas.pydata.org/pandas-docs/stable/generated/pandas.read_csv.html

[toc] | [prev] | [next] | [standalone]

#98743

On Thu, 12 Nov 2015 21:27:58 -0800, Karthik Sharma wrote:

> I have some csv data in the following format. ......

Does the following idea help?

Create a key from the key fields, remove the key fields from the row dic 
(so now it's a dic of just the data fields), and save that in the 
plotdata dict keyed by the key.

import csv

keybits = ["Ln","Dr","Tag","Lab"]

plotdata = {}

with open("lab.csv", 'r') as fin:
    reader = csv.DictReader(fin)
    for row in reader:
        key = tuple([row[k] for k in keybits])
        for k in keybits:
            del row[k]
        plotdata[key] = row

This generates a dictionary (plotdata) keyed by the key tuples where the 
value for each key is a dictionary of 0:0n : value

-- 
Denis McMahon, denismfmcmahon@gmail.com

[toc] | [prev] | [standalone]

Back to top | Article view | comp.lang.python

csiph-web