@@ -276,7 +276,7 @@ print(result)
276276
277277## Processing Files Based on Record Length
278278
279- Modify this program so that it only processes files with fewer than 50 records.
279+ Modify this program so that it only processes files with fewer than 85 records.
280280
281281``` python
282282import glob
@@ -344,58 +344,6 @@ print(smallest, largest)
344344
345345:::::::::::::::::::::::::
346346
347- ::::::::::::::::::::::::::::::::::::::::::::::::::
348-
349- ::::::::::::::::::::::::::::::::::::::::: callout
350-
351- ## Using Functions With Conditionals in Pandas
352-
353- Functions will often contain conditionals. Here is a short example that
354- will indicate which quartile the argument is in based on hand-coded values
355- for the quartile cut points.
356-
357- ``` python
358- def calculate_life_quartile (exp ):
359- if exp < 58.41 :
360- # This observation is in the first quartile
361- return 1
362- elif exp >= 58.41 and exp < 67.05 :
363- # This observation is in the second quartile
364- return 2
365- elif exp >= 67.05 and exp < 71.70 :
366- # This observation is in the third quartile
367- return 3
368- elif exp >= 71.70 :
369- # This observation is in the fourth quartile
370- return 4
371- else :
372- # This observation has bad data
373- return None
374-
375- calculate_life_quartile(62.5 )
376- ```
377-
378- ``` output
379- 2
380- ```
381-
382- That function would typically be used within a ` for ` loop, but Pandas has
383- a different, more efficient way of doing the same thing, and that is by
384- * applying* a function to a dataframe or a portion of a dataframe. Here
385- is an example, using the definition above.
386-
387- ``` python
388- data = pd.read_csv(' Americas-data.csv' )
389- data[' life_qrtl' ] = data[' lifeExp' ].apply(calculate_life_quartile)
390- ```
391-
392- There is a lot in that second line, so let's take it piece by piece.
393- On the right side of the ` = ` we start with ` data['lifeExp'] ` , which is the
394- column in the dataframe called ` data ` labeled ` lifExp ` . We use the
395- ` apply() ` to do what it says, apply the ` calculate_life_quartile ` to the
396- value of this column for every row in the dataframe.
397-
398-
399347::::::::::::::::::::::::::::::::::::::::::::::::::
400348
401349:::::::::::::::::::::::::::::::::::::::: keypoints
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