Bottom Page

Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
 How do I map a list of values to specified colors?
Here is what I want to do:
a list of 19 values:
[-1, 1, -2, 2, -3, 3, -4, 4, -5, 5, -6, 6, -7, 7, -8, 8, -9, 9, 0]
I would like the color grey gradual from white to black in the order in the list. How can I do that?
or else, if I can specify each different color to each different values, that is also ok.

what have you tried?
Thanks, Larz60+, What I am thinking about is mapping the list
[-1, 1, -2, 2, -3, 3, -4, 4, -5, 5, -6, 6, -7, 7, -8, 8, -9, 9, 0] to another list
[255//19*i for i in range(19)] first
and then use
plt.imshow(arr, cmap='gray', vmin=0, vmax=255//19*19)
to show the array

I felt this method is not direct. Is there any better method, I mean directly assign a color to that number in the original list.

Thank you very much!
is this what you are looking for?
>>> import numpy as np
>>> delta = 0.025
>>> x = y = np.arange(-3.0, 3.0, delta)
>>> x
array([-3.0000000e+00, -2.9750000e+00, -2.9500000e+00, -2.9250000e+00,
       -2.9000000e+00, -2.8750000e+00, -2.8500000e+00, -2.8250000e+00,
       -2.8000000e+00, -2.7750000e+00, -2.7500000e+00, -2.7250000e+00,
       -2.7000000e+00, -2.6750000e+00, -2.6500000e+00, -2.6250000e+00,
       -2.6000000e+00, -2.5750000e+00, -2.5500000e+00, -2.5250000e+00,
       -2.5000000e+00, -2.4750000e+00, -2.4500000e+00, -2.4250000e+00,
       -2.4000000e+00, -2.3750000e+00, -2.3500000e+00, -2.3250000e+00,
       -2.3000000e+00, -2.2750000e+00, -2.2500000e+00, -2.2250000e+00,
       -2.2000000e+00, -2.1750000e+00, -2.1500000e+00, -2.1250000e+00,
       -2.1000000e+00, -2.0750000e+00, -2.0500000e+00, -2.0250000e+00,
       -2.0000000e+00, -1.9750000e+00, -1.9500000e+00, -1.9250000e+00,
       -1.9000000e+00, -1.8750000e+00, -1.8500000e+00, -1.8250000e+00,
       -1.8000000e+00, -1.7750000e+00, -1.7500000e+00, -1.7250000e+00,
       -1.7000000e+00, -1.6750000e+00, -1.6500000e+00, -1.6250000e+00,
       -1.6000000e+00, -1.5750000e+00, -1.5500000e+00, -1.5250000e+00,
       -1.5000000e+00, -1.4750000e+00, -1.4500000e+00, -1.4250000e+00,
       -1.4000000e+00, -1.3750000e+00, -1.3500000e+00, -1.3250000e+00,
       -1.3000000e+00, -1.2750000e+00, -1.2500000e+00, -1.2250000e+00,
       -1.2000000e+00, -1.1750000e+00, -1.1500000e+00, -1.1250000e+00,
       -1.1000000e+00, -1.0750000e+00, -1.0500000e+00, -1.0250000e+00,
       -1.0000000e+00, -9.7500000e-01, -9.5000000e-01, -9.2500000e-01,
       -9.0000000e-01, -8.7500000e-01, -8.5000000e-01, -8.2500000e-01,
       -8.0000000e-01, -7.7500000e-01, -7.5000000e-01, -7.2500000e-01,
       -7.0000000e-01, -6.7500000e-01, -6.5000000e-01, -6.2500000e-01,
       -6.0000000e-01, -5.7500000e-01, -5.5000000e-01, -5.2500000e-01,
       -5.0000000e-01, -4.7500000e-01, -4.5000000e-01, -4.2500000e-01,
       -4.0000000e-01, -3.7500000e-01, -3.5000000e-01, -3.2500000e-01,
       -3.0000000e-01, -2.7500000e-01, -2.5000000e-01, -2.2500000e-01,
       -2.0000000e-01, -1.7500000e-01, -1.5000000e-01, -1.2500000e-01,
       -1.0000000e-01, -7.5000000e-02, -5.0000000e-02, -2.5000000e-02,
       -1.0658141e-14,  2.5000000e-02,  5.0000000e-02,  7.5000000e-02,
        1.0000000e-01,  1.2500000e-01,  1.5000000e-01,  1.7500000e-01,
        2.0000000e-01,  2.2500000e-01,  2.5000000e-01,  2.7500000e-01,
        3.0000000e-01,  3.2500000e-01,  3.5000000e-01,  3.7500000e-01,
        4.0000000e-01,  4.2500000e-01,  4.5000000e-01,  4.7500000e-01,
        5.0000000e-01,  5.2500000e-01,  5.5000000e-01,  5.7500000e-01,
        6.0000000e-01,  6.2500000e-01,  6.5000000e-01,  6.7500000e-01,
        7.0000000e-01,  7.2500000e-01,  7.5000000e-01,  7.7500000e-01,
        8.0000000e-01,  8.2500000e-01,  8.5000000e-01,  8.7500000e-01,
        9.0000000e-01,  9.2500000e-01,  9.5000000e-01,  9.7500000e-01,
        1.0000000e+00,  1.0250000e+00,  1.0500000e+00,  1.0750000e+00,
        1.1000000e+00,  1.1250000e+00,  1.1500000e+00,  1.1750000e+00,
        1.2000000e+00,  1.2250000e+00,  1.2500000e+00,  1.2750000e+00,
        1.3000000e+00,  1.3250000e+00,  1.3500000e+00,  1.3750000e+00,
        1.4000000e+00,  1.4250000e+00,  1.4500000e+00,  1.4750000e+00,
        1.5000000e+00,  1.5250000e+00,  1.5500000e+00,  1.5750000e+00,
        1.6000000e+00,  1.6250000e+00,  1.6500000e+00,  1.6750000e+00,
        1.7000000e+00,  1.7250000e+00,  1.7500000e+00,  1.7750000e+00,
        1.8000000e+00,  1.8250000e+00,  1.8500000e+00,  1.8750000e+00,
        1.9000000e+00,  1.9250000e+00,  1.9500000e+00,  1.9750000e+00,
        2.0000000e+00,  2.0250000e+00,  2.0500000e+00,  2.0750000e+00,
        2.1000000e+00,  2.1250000e+00,  2.1500000e+00,  2.1750000e+00,
        2.2000000e+00,  2.2250000e+00,  2.2500000e+00,  2.2750000e+00,
        2.3000000e+00,  2.3250000e+00,  2.3500000e+00,  2.3750000e+00,
        2.4000000e+00,  2.4250000e+00,  2.4500000e+00,  2.4750000e+00,
        2.5000000e+00,  2.5250000e+00,  2.5500000e+00,  2.5750000e+00,
        2.6000000e+00,  2.6250000e+00,  2.6500000e+00,  2.6750000e+00,
        2.7000000e+00,  2.7250000e+00,  2.7500000e+00,  2.7750000e+00,
        2.8000000e+00,  2.8250000e+00,  2.8500000e+00,  2.8750000e+00,
        2.9000000e+00,  2.9250000e+00,  2.9500000e+00,  2.9750000e+00])
Thanks MckJohan, but nope. What I want to do is to specify a certain value to a specified color, maybe through RGB values.
establish the connections like the following:
-1 ---------------> R200 G150 B0
1 ---------------> R....G....B...
Something like this, and then use the map to draw

Top Page

Possibly Related Threads...
Thread Author Replies Views Last Post
  access dictionary with keys from another and write values to list redminote4dd 6 213 Jun-03-2020, 05:20 PM
Last Post: DeaD_EyE
  Grabbing comma separed values from SQLite and putting them in a list PythonNPC 8 359 Apr-10-2020, 02:39 PM
Last Post: buran
  Randomly assign values in List 1 to a value in List 2 Seneca260 7 856 Dec-16-2019, 12:57 PM
Last Post: BamBi25
  Why does this list of lists end up with the same values alehak 2 590 Jul-18-2019, 12:34 PM
Last Post: perfringo
  How to create a list with all values being zero 357mag 4 488 Jul-14-2019, 03:43 PM
Last Post: ThomasL
  Remove \n from list of values within a pandas columns klllmmm 2 2,414 Jun-24-2019, 05:16 AM
Last Post: klllmmm
  update values in list based on dictionary bunti 3 1,066 Jun-10-2019, 07:26 AM
Last Post: perfringo
  after using openpyxl to add colors to script, black shows up white online in excel Soundtechscott 1 800 Jun-08-2019, 10:33 PM
Last Post: Soundtechscott
  count unique values of a list with a list 3Pinter 2 2,540 Jul-05-2018, 11:52 AM
Last Post: 3Pinter
  Looping through dictionary and comparing values with elements of a separate list. Mr_Keystrokes 5 1,016 Jun-22-2018, 03:08 PM
Last Post: wavic

Forum Jump:

Users browsing this thread: 1 Guest(s)