如何根据 Python pandas DataFrame 中的单元格的值对不同的单元格进行着色

Question

I have a pandas DataFrame with different string values to be filled by different colors. For the following DataFrame df , all I want is that different cells are in different colors. For example, the cells that have 'A' value is in red, the cells that have 'B' value is in green, and 'C' in blue, 'D' in grey, etc.

df=pd.DataFrame({'a':['A','B','D'],'b':['E','B','C'],'c':['F','A','D']})

How can I achieve this using the Styler.apply ? Any thoughts?

Answer 1

try:

col_dict = {'A': 'red', 'B': 'green', 'C': 'blue', 'D': 'gray'}
def colour_cell(val):
    if val in col_dict:
        return 'Background-color: %s' % col_dict[val]
    return ''

---

df.style.applymap(colour_cell)

One liner solution(assuming if all the values will have color assigned to it):

df.style.applymap(lambda v: 'Background-color: %s' % col_dict[v])

Answer 2

You could use Styling with a dictionary of colors you want to map values to:

import pandas as pd

d = {'a': ['A', 'B', 'D'], 'b': ['E', 'B', 'C'], 'c': ['F', 'A', 'D']}
df = pd.DataFrame(data=d)
df

color_mapping = {'A': 'red', 'B': 'green', 'C': 'blue', 'D': 'gray', 'E': 'indigo', 'F': 'violet'}
df.style.applymap(lambda v: f"color: {color_mapping.get(v, 'black')}")

If you want the cells to be filled in with the color use background-color rather than color :

df.style.applymap(lambda v: f"background-color: {color_mapping.get(v, 'black')}")

In case you want to set background color and the text color to white for better readability:

df.style.applymap(lambda v: f"background-color: {color_mapping.get(v, 'black')}").applymap(lambda _: "color: white")