You may want to edit a sample or subgroup of data in WinSPC after that data has already been collected. Assuming you use a login with sufficient permission to do so, you can edit data for previously collected data. 

To edit data, you need access to the Data Point Viewer (or just Data Viewer). Depending on what version of WinSPC you are currently on and the permission a given user has, the Data Viewer can be accessed from almost anywhere you can access a WinSPC chart, including:

• Data Collection
• Plant Monitor
• Legacy Query Tool
• Variable Analyzer (version 8.2 and above)

NOTE: Variable Analyzer's uses an enhanced version of the Data Point Viewer. For more information on this, please reference the following Knowledgebase article: https://knowledgebase.winspc.com/questions/283 

1. Display the chart containing the variable or attribute data point you want to edit. You may display this chart in the "Data Collection" window, on the "Charts" tab of the "Violation Browser" in the "Plant Monitor", or in the "Query Tool".
2. On the chart, click the variable or attribute data point you want to edit. This displays the "Data Viewer".
   
   



3. In the "Data" column at the top, overwrite the value you want to change.
4. If you would like to add or edit an "Assignable Cause", "Corrective Action" or "Note", do so while you have the "Data Viewer" displayed in the lower portion of the dialog box.
5. Click "OK". The "Data Viewer" closes, the chart is redrawn using the edited value and an Edit marker is added near the data point you edited.
   
   

NOTE: The Data, Date, Time, User and Station will all change based on who, what, where and when the edited data was entered.

If you ever want to view the original data along with the original date, time, user and station, you can click an edited data point to bring up the "Data Viewer" and either scroll to the right or increase the size of the "Data Viewer" window until the "Data (original)" "Date (original)", "Time (original)", "User (original)" and "Station (original)" columns are visible.


If you have your Audit Trail (Event Log) enabled in WinSPC's 'System Settings' you can also access edited data by filtering to the date range where your edit occured. (You can further filter based on other criteria that apply to you).