python-3.x - Lambda Function To Categorise Terms Causing NameError

Question

I'm trying to tag some keywords by topic using some regex strings that they might contain. This will ideally append a "Category" column to the dataframe with either the tag that it falls into or "other" if none was found.

The data I'm trying to tag basically looks like the following:

| Keyword    |      Volume |
|:-----------|------------:|
| audi specs |        4000 |
| bmw width  |         170 |
| a45 bhp    |          30 |
| a1 length  |         210 |
| alfa co2   |          10 |

And the code I've got currently is:

import pandas as pd
import numpy as np
import re
from IPython.display import display

df = pd.read_csv("make-model-keywords.csv")
df = pd.DataFrame(df, columns=['Keyword', 'Volume','Keyword Difficulty','CPC (USD)', 'SERP Features'])

tags = [
{
    "name": "Dimensions",
    "regex": "dimension|width|height|length|size"
},
{
    "name": "MPG",
    "regex": "mpg|co2|emission|consumption|running|economy|fuel"
},
{
    "name": "Specs",
    "regex": "spec|specification|torque|bhp|weight|rpm|62|mph|kmh"
}
]

def basic_tagging(string, tags):
for tag in tags:
    if re.match(tag['regex'], row['Keyword']):
        return tag['name']
    else:
        return "other"

df['Category'] = df.apply(lambda x: basic_tagging(x['Keyword'], tags), axis=1)

However it's giving me the following error:

---------------------------------------------------------------
NameError                     Traceback (most recent call last)
<ipython-input-71-31890ef48022> in <module>()
----> 1 df['Category'] = df.apply(lambda row: basic_tagging(row['Keyword'],         tags), axis=1)
  2 df.head()

~\AppData\Local\Continuum\anaconda3\lib\site-packages\pandas\core\frame.py in apply(self, func, axis, broadcast, raw, reduce, result_type, args, **kwds)
   6012                          args=args,
   6013                          kwds=kwds)
-> 6014         return op.get_result()
   6015 
   6016     def applymap(self, func):

~\AppData\Local\Continuum\anaconda3\lib\site-packages\pandas\core\apply.py in get_result(self)
    140             return self.apply_raw()
    141 
--> 142         return self.apply_standard()
    143 
    144     def apply_empty_result(self):

~\AppData\Local\Continuum\anaconda3\lib\site-packages\pandas\core\apply.py in apply_standard(self)
    246 
    247         # compute the result using the series generator
--> 248         self.apply_series_generator()
    249 
    250         # wrap results

~\AppData\Local\Continuum\anaconda3\lib\site-packages\pandas\core\apply.py in apply_series_generator(self)
    275             try:
    276                 for i, v in enumerate(series_gen):
--> 277                     results[i] = self.f(v)
    278                     keys.append(v.name)
    279             except Exception as e:

<ipython-input-71-31890ef48022> in <lambda>(row)
----> 1 df['Category'] = df.apply(lambda row: basic_tagging(row['Keyword'], tags), axis=1)
  2 df.head()

<ipython-input-68-1867110ca579> in basic_tagging(string, tags)
      1 def basic_tagging(string, tags):
      2     for tag in tags:
----> 3         if re.match(tag['regex'], row['Keyword']):
      4             return tag['name']
      5         else:

NameError: ("name 'row' is not defined", 'occurred at index 0')

Is there something patently obvious that I'm missing?

标签： python-3.xpandasjupyter-notebook

Answer 1

将您的功能更改为：

def basic_tagging(row):
    for tag in tags:
        if re.match(tag['regex'], row['Keyword']):
            return tag['name']
        else:
            return "other"

接着：

df['Category'] = df.apply(basic_tagging, axis=1)