How to get a dict with index and value of certain column-CodePudding

I have this toy dataset:

cat         count   class_weight
cars        17824    0.000404
bus         124784   0.000553
planes      111271   0.000620

I want to output a dictionary with index and class_weight values, like this:

 {0: 0.000404,
    1: 0.000553,
    2: 0.000620}

I am doing:

class_weight = {}
for index, label in enumerate(categories):
    class_weight[index] = df[df['cat'] == categories]['class_weight'].values[0]

categories is a numpy.ndarray with the cat values

and my output is wrong because the values[0 is returning the first value for all car items:

   {0: 0.000404,
    1: 0.000404,
    2: 0.000404}

How can I fix it?

CodePudding user response：

pd.Series.to_dict's default output is what you're looking for.

Given:

      cat   count  class_weight
0    cars   17824      0.000404
1     bus  124784      0.000553
2  planes  111271      0.000620

Doing:

x = df.class_weight.to_dict()
print(x)

Output:

{
 0: 0.000404, 
 1: 0.000553, 
 2: 0.00062
}