R/reformat_data.R
    reformat_data.RdReformats data for analysis by changing column names and filtering out non-arm's length sales.
reformat_data( data, sale_col, assessment_col, sale_year_col, filter_data = TRUE )
| data | a dataframe with assessment, sales, and time data | 
|---|---|
| sale_col | the name of the column with sales data | 
| assessment_col | the name of the column with assessment data | 
| sale_year_col | the name of the column with the year of sale | 
| filter_data | optional, default True. if True, keeps only arm's length sales. if False, keeps all data. | 
a dataframe with appropriate column names and arm's length markings