I am trying to determine the color of borders set in an Excel document. I use the 'openpyxl' library (latest Version 3.0.9) and encountered a problem to extract the rgb color code when the user sets the border via the default 'auto' color.
When I extract the cell color property, I see this (in my debugger, see screenshot). None of the cell fields are set with an RGB code, the fields indicate some problem with extracting the color information. I assume this is due to the 'auto' color.
The index color probably refers to this in documentation:
Default Color Index as per 18.8.27 of ECMA Part 4
COLOR_INDEX = (
'00000000', '00FFFFFF', '00FF0000', '0000FF00', '000000FF', #0-4
'00FFFF00', '00FF00FF', '0000FFFF', '00000000', '00FFFFFF', #5-9
'00FF0000', '0000FF00', '000000FF', '00FFFF00', '00FF00FF', #10-14
'0000FFFF', '00800000', '00008000', '00000080', '00808000', #15-19
'00800080', '00008080', '00C0C0C0', '00808080', '009999FF', #20-24
'00993366', '00FFFFCC', '00CCFFFF', '00660066', '00FF8080', #25-29
'000066CC', '00CCCCFF', '00000080', '00FF00FF', '00FFFF00', #30-34
'0000FFFF', '00800080', '00800000', '00008080', '000000FF', #35-39
'0000CCFF', '00CCFFFF', '00CCFFCC', '00FFFF99', '0099CCFF', #40-44
'00FF99CC', '00CC99FF', '00FFCC99', '003366FF', '0033CCCC', #45-49
'0099CC00', '00FFCC00', '00FF9900', '00FF6600', '00666699', #50-54
'00969696', '00003366', '00339966', '00003300', '00333300', #55-59
'00993300', '00993366', '00333399', '00333333', #60-63
)
# indices 64 and 65 are reserved for the system foreground and background colours respectively
The documentation says that Index 64 is reserved so there is no point in trying to access the color array (max index is 63).
Source: https://openpyxl.readthedocs.io/en/stable/_modules/openpyxl/styles/colors.html
I can be brave and deal with index 64 as black, which seems to be the eternal auto-color anyway but I am wondering if there is a proper way to decode the 'auto' color from Excel?
System colours are set by the application. Windows defaults will be white background and black foreground. You can check the colors part of the styles.xml to see if these have been overriden, but really the client application gets to decide.
I am using Altair for Python and my current code uses a redyellowblue color scheme which uses the middle color (yellow) accordingly to my domainMid parameter.
color=alt.Color('Spline_WW_Diff_Trend:Q', scale=alt.Scale(scheme='redyellowblue',reverse=True, domain=[-3.57,2.270], domainMid=0, clamp=True), legend=alt.Legend(title="Trend"))
Which gives me:
I need to replace the yellow color with the white color. I've switched scheme to range and tried different combinations of Scale parameters, but it doesn't respect my domainMid.
Example:
color=alt.Color('Spline_WW_Diff_Trend:Q', scale=alt.Scale(range=['#D4322C', 'white', '#4A74B4'],reverse=True, domain=[-3.57,2.270], domainMid=0, clamp=True), legend=alt.Legend(title="Trend"))
This gives me:
You can notice that the first column (which is all value 0) is showing reddish and not white (as it was supposed to be).
How can I have the same result as in the color scheme (picture one), but, with white instead of yellow?
Edit:
The same goes for.
range=['blue', 'lightblue', 'white', 'pink', 'red']
The mid color is light-blue, not white.
Edit 05/12/2022:
Just to clarify, I would like to achieve this same color scheme:
.
This heatmap was created in R, by using the RdYlBu color pallete (the one with 11 colors) and overwrite the middle (6th color) with white. Then, they increased the number of colors in the pallete to 99, to make the fade look more fluid. Does anyone has any idea on how to achieve that in Altair?
The easiest approach would be to set range='diverging', or to use one of the built-in diverging color schemes. For example:
import altair as alt
import pandas as pd
import numpy as np
df = pd.DataFrame({'x': np.arange(-10, 20)})
alt.Chart(df).mark_rect().encode(
x='x:O',
color=alt.Color('x:Q',
scale=alt.Scale(domainMid=0, scheme='redblue'))
)
If it's important to you that the center value is exactly white, you could use a condition to override the colormap for this value. For example:
alt.Chart(df).mark_rect().encode(
x='x:O',
color=alt.condition(
'datum.x == 0',
alt.value('white'),
alt.Color('x:Q', scale=alt.Scale(domainMid=0, scheme='redblue')))
)
I am trying to set up a series of vertical axis spans to symbolize different switching positions at different times. For example, in the figure below, switching position 1 (green) happens quite a few times, alternating between other positions.
I plot these spans running a for loop in a list of tuples, each containing the initial and final indexes of each interval to plot the axvspan.
def plotShades(timestamp, intervals, colour):
for i in range(len(intervals)):
md.plt.axvspan(timestamp[intervals[i][0]], timestamp[intervals[i][1]], alpha=0.5, color=colour, label="interval")
This function is then called upon another one, that plots the shades for each different switching position:
def plotAllOutcomes(timestamp, switches):
#switches is a list of 7 arrays indicating when the switcher is at each one of the 7 positions. If the array has a 1 value, the switcher is there. 0 otherwise.
colors = ['#d73027', '#fc8d59', '#fee08b', '#ffffbf', '#d9ef8b', '#91cf60', '#1a9850']
intervals = []
for i in range(len(switches)):
intervals.append(getIntervals(switches[i], timestamp))
plotShades(timestamp, intervals[i], colors[i])
md.plt.legend()
Doing so with the code snippets I've put here (not the best code, I know - I'm fairly new in Python!) the legend ends up having one item for each interval, and that's pretty awful. This is how it looks:
I'd like to get a legend with only 7 items, each for a single color in my plot of axvspans. How can I proceed to do so? I've searched quite extensively but haven't managed to find this situation being asked before. Thank you in advance for any help!!
A small trick you can apply using the fact that labels starting with "_" are ignored:
plt.axvspan( ... , label = "_"*i + "interval")
Thereby a label is only created for the case where i==0.
I'm attempting to reverse engineer a file format from a logging program. It seems to use a 1-2 byte field which may be used for label colors, as it seems to be the only thing that's unexplained. Short of iterating through other label colors and generating new output files (which is a pain in the ass, hence me trying to reverse-engineer the format in the first place), are there any standard 8-bit color palettes they may line up with? I've found some (e.g. the only 216 colors that are allowed on the web), but they're not enumerated in any particular way.
I believe 0x32 is light green (e.g. 0,255,0), 0x0A is teal cyan (0, 255, 255), and 0x28 is red. Each field may also include a trailing 0x00.
Or I could be totally wrong.
Well, it could be one of the old standard VGA palettes. This is the one for mode 13h:
However, the numbers you posted seem to be off-by-one from the index into the usual ordering.
EDIT: Here are the 24-bit RGB values for the color components in a python formatted array. It is a bit long so be warned!
[0x000000, 0x0000a8, 0x00a800, 0x00a8a8, 0xa80000, 0xa800a8, 0xa85400, 0xa8a8a8, 0x545454, 0x5454fc, 0x54fc54, 0x54fcfc, 0xfc5454, 0xfc54fc, 0xfcfc54, 0xfcfcfc, 0x000000, 0x141414, 0x202020, 0x2c2c2c, 0x383838, 0x444444, 0x505050, 0x606060, 0x707070, 0x808080, 0x909090, 0xa0a0a0, 0xb4b4b4, 0xc8c8c8, 0xe0e0e0, 0xfcfcfc, 0x0000fc, 0x4000fc, 0x7c00fc, 0xbc00fc, 0xfc00fc, 0xfc00bc, 0xfc007c, 0xfc0040, 0xfc0000, 0xfc4000, 0xfc7c00, 0xfcbc00, 0xfcfc00, 0xbcfc00, 0x7cfc00, 0x40fc00, 0x00fc00, 0x00fc40, 0x00fc7c, 0x00fcbc, 0x00fcfc, 0x00bcfc, 0x007cfc, 0x0040fc, 0x7c7cfc, 0x9c7cfc, 0xbc7cfc, 0xdc7cfc, 0xfc7cfc, 0xfc7cdc, 0xfc7cbc, 0xfc7c9c, 0xfc7c7c, 0xfc9c7c, 0xfcbc7c, 0xfcdc7c, 0xfcfc7c, 0xdcfc7c, 0xbcfc7c, 0x9cfc7c, 0x7cfc7c, 0x7cfc9c, 0x7cfcbc, 0x7cfcdc, 0x7cfcfc, 0x7cdcfc, 0x7cbcfc, 0x7c9cfc, 0xb4b4fc, 0xc4b4fc, 0xd8b4fc, 0xe8b4fc, 0xfcb4fc, 0xfcb4e8, 0xfcb4d8, 0xfcb4c4, 0xfcb4b4, 0xfcc4b4, 0xfcd8b4, 0xfce8b4, 0xfcfcb4, 0xe8fcb4, 0xd8fcb4, 0xc4fcb4, 0xb4fcb4, 0xb4fcc4, 0xb4fcd8, 0xb4fce8, 0xb4fcfc, 0xb4e8fc, 0xb4d8fc, 0xb4c4fc, 0x000070, 0x1c0070, 0x380070, 0x540070, 0x700070, 0x700054, 0x700038, 0x70001c, 0x700000, 0x701c00, 0x703800, 0x705400, 0x707000, 0x547000, 0x387000, 0x1c7000, 0x007000, 0x00701c, 0x007038, 0x007054, 0x007070, 0x005470, 0x003870, 0x001c70, 0x383870, 0x443870, 0x543870, 0x603870, 0x703870, 0x703860, 0x703854, 0x703844, 0x703838, 0x704438, 0x705438, 0x706038, 0x707038, 0x607038, 0x547038, 0x447038, 0x387038, 0x387044, 0x387054, 0x387060, 0x387070, 0x386070, 0x385470, 0x384470, 0x505070, 0x585070, 0x605070, 0x685070, 0x705070, 0x705068, 0x705060, 0x705058, 0x705050, 0x705850, 0x706050, 0x706850, 0x707050, 0x687050, 0x607050, 0x587050, 0x507050, 0x507058, 0x507060, 0x507068, 0x507070, 0x506870, 0x506070, 0x505870, 0x000040, 0x100040, 0x200040, 0x300040, 0x400040, 0x400030, 0x400020, 0x400010, 0x400000, 0x401000, 0x402000, 0x403000, 0x404000, 0x304000, 0x204000, 0x104000, 0x004000, 0x004010, 0x004020, 0x004030, 0x004040, 0x003040, 0x002040, 0x001040, 0x202040, 0x282040, 0x302040, 0x382040, 0x402040, 0x402038, 0x402030, 0x402028, 0x402020, 0x402820, 0x403020, 0x403820, 0x404020, 0x384020, 0x304020, 0x284020, 0x204020, 0x204028, 0x204030, 0x204038, 0x204040, 0x203840, 0x203040, 0x202840, 0x2c2c40, 0x302c40, 0x342c40, 0x3c2c40, 0x402c40, 0x402c3c, 0x402c34, 0x402c30, 0x402c2c, 0x40302c, 0x40342c, 0x403c2c, 0x40402c, 0x3c402c, 0x34402c, 0x30402c, 0x2c402c, 0x2c4030, 0x2c4034, 0x2c403c, 0x2c4040, 0x2c3c40, 0x2c3440, 0x2c3040, 0x000000, 0x000000, 0x000000, 0x000000, 0x000000, 0x000000, 0x000000, 0x000000]
There is no standard palette for 8-bit but Teletext uses true 8-bit color palette
It's based on hardwares
http://en.wikipedia.org/wiki/List_of_8-bit_computer_hardware_palettes
Edit : Some devices able to show different shades of color by adjusting brightness but true 8-bit is this palette ( Teletext )