[Tutor] Shading Between Curves with Different Colour Over Specified X value Range

Oscar Benjamin oscar.j.benjamin at gmail.com
Tue Jul 28 16:03:48 CEST 2015


On Mon, 27 Jul 2015 at 20:53 Colin Ross <colin.ross.dal at gmail.com> wrote:

> *Goal:* Shade between I_2 (curve 1) and I_3 (curve 2) with following
> conditions:
>                                               - Green for 0 < x < 4
>                                               - Red for 4 < x < 12
>
> *Code: *
>
> *Note: Code currently only attempting to shade green for 0 < x < 4 *
>
> import numpy as np
> import pylab
> from pylab import *
> import matplotlib.pyplot as plt
> import csv
>
>
> # Load data from .txt file
>
> with open('current_mirror_output_swing.csv', 'rb') as f:
>    reader = csv.reader(f)
>    your_list = list(reader)
>
> data = np.asarray(your_list)
>
> I_ref = np.asarray(data[1:,0])
> I_1 = data[1:,1]
> I_2 = data[1:,2]
> I_3 = data[1:,3]
>
> # Create an array of x values to fill b/w curves with a certain color.
>
>
Here you specify the X values for the fill shape as going from 0 to 4:


> X1 = np.linspace(0.,4.,len(I_3))
>
> I_ref = I_ref.astype(float)*1000.
> I_1 = I_1.astype(float)*1000.
> I_2 = I_2.astype(float)*1000.
> I_3 = I_3.astype(float)*1000.
>
>
> # Plotting commands.
>
>
Here you specify the X values for the line plots as being whatever I_ref is
(I don't know what it is since I can't see your csv file):


> plot(I_ref, I_2, 'r-')
> plot(I_ref, I_3, 'b-')
> title('Current Mirror Output Swing')
> xlabel('$I_{ref}$ (mA)')
> ylabel('I (mA)')
>
>
Try changing this line:


> plt.fill_between(X1, I_2, I_3, color = 'g', alpha = '0.5')
>

to:

    plt.fill_between(I_ref, I_2, I_3, color = 'g', alpha = '0.5')

and then the filled area should have the same X range as the lines.

--
Oscar


More information about the Tutor mailing list