| agg | Aggregate an Atomic Vector by Group |
| aggs | Aggregate Data by Group |
| agg_dfm | Data Information by Group |
| ave_dfm | Repeated Group Statistics for a Data-Frame |
| by2 | Apply a Function to Data by Group |
| center | Centering and/or Standardizing a Numeric Vector |
| centers | Centering and/or Standardizing Numeric Data |
| centers_by | Centering and/or Standardizing Numeric Data by Group |
| center_by | Centering and/or Standardizing a Numeric Vector by Group |
| change | Change Score from a Numeric Vector |
| changes | Change Scores from Numeric Data |
| changes_by | Change Scores from Numeric Data by Group |
| change_by | Change Scores from a Numeric Vector by Group |
| colMeans_if | Column Means Conditional on Frequency of Observed Values |
| colNA | Frequency of Missing Values by Column |
| colSums_if | Column Sums Conditional on Frequency of Observed Values |
| decompose | Decompose a Numeric Vector by Group |
| decomposes | Decompose Numeric Data by Group |
| dum2nom | Dummy Variables to a Nominal Variable |
| freq | Univariate Frequency Table |
| freqs | Multiple Univariate Frequency Tables |
| freqs_by | Multiple Univariate Frequency Tables |
| freq_by | Univariate Frequency Table By Group |
| long2wide | Reshape Multiple Scores From Long to Wide |
| make.dummy | Make Dummy Columns |
| make.dumNA | Make Dummy Columns For Missing Data. |
| make.fun_if | Make a Function Conditional on Frequency of Observed Values |
| make.product | Make Product Terms (e.g., interactions) |
| mean_if | Mean Conditional on Minimum Frequency of Observed Values |
| mode2 | Statistical Mode of a Numeric Vector |
| ncases | Number of Cases in Data |
| nom2dum | Nominal Variable to Dummy Variables |
| partial.cases | Find Partial Cases |
| pomp | Recode a Numeric Vector to Percentage of Maximum Possible (POMP) Units |
| pomps | Recode Numeric Data to Percentage of Maximum Possible (POMP) Units |
| quest | Pre-processing Questionnaire Data |
| recode2other | Recode Unique Values in a Character Vector to 0ther (or NA) |
| recodes | Recode Data |
| renames | Rename Data Columns from a Codebook |
| reorders | Reorder Levels of Factor Data |
| revalid | Recode Invalid Values from a Vector |
| revalids | Recode Invalid Values from Data |
| reverse | Reverse Code a Numeric Vector |
| reverses | Reverse Code Numeric Data |
| rowMeans_if | Row Means Conditional on Frequency of Observed Values |
| rowNA | Frequency of Missing Values by Row |
| rowsNA | Frequency of Multiple Sets of Missing Values by Row |
| rowSums_if | Row Sums Conditional on Frequency of Observed Values |
| score | Observed Unweighted Scoring of a Set of Variables/Items |
| scores | Observed Unweighted Scoring of Multiple Sets of Variables/Items |
| shift | Shift a Vector (i.e., lag/lead) |
| shifts | Shift Data (i.e., lag/lead) |
| shifts_by | Shift Data (i.e., lag/lead) by Group |
| shift_by | Shift a Vector (i.e., lag/lead) by Group |
| sum_if | Sum Conditional on Minimum Frequency of Observed Values |
| tapply2 | Apply a Function to a (Atomic) Vector by Group |
| valids_test | Test for Invalid Elements in Data |
| valid_test | Test for Invalid Elements in a Vector |
| vecNA | Frequency of Missing Values in a Vector |
| wide2long | Reshape Multiple Sets of Variables From Wide to Long |
| winsor | Winsorize a Numeric Vector |
| winsors | Winsorize Numeric Data |