Manage Missing Values and Errors when Loading Data

Missing values or error messages occur when there is no data value found for a specific column or if an error occurred while trying to convert the found data value to the column's data type.

Missing values are not supported for integer data and boolean data. Missing values are supported only for floating point data (double and single data type) and for string data (string data type). If you have integer data and want to use missing values you have to make the data type float or double.

The way missing values are interpreted can be modified in the No Value column in the Column Definition Table.

Missing Entries

Floating Data Type

No Value Column Option	Interpretation	Comments
Missing	No data present.	No calculation uses this data point. A Data Column Component with this column contains no points for missing entries, so there are fewer points than samples.
Default	The default numeric value is applied to the missing entry.	All loaded samples are used with missing entries set to the default value.
Error	A load error generates and the point is interpreted as in missing.	Load errors are reported in the Load Summary Window.

String Data Type

No Value Column Option	Interpretation	Comments
Missing	No data present.	No data is used for this point. This includes data filters and grouping domain data.
Default	The default string value is applied to the missing entry.	All loaded samples are used with missing entries set to the default value. An empty default value is used like another valid value for this column. It is used in data grouping and is a unique value for categorical data.
Error	A load error generates and the point is interpreted as in missing.	Load errors are reported in the Load Summary Window.

Integer Data Type

No Value Column Option	Interpretation	Comments
Default	The default numeric value is applied to the missing entry.	Missing values are not allowed for integer data.
Error	A load error generates and the point is set to zero (0).	Load errors are reported in the Load Summary Window.

Boolean Data Type

No Value Column Option	Interpretation	Comments
Default	The default numeric value is applied to the missing entry. False is used if no specific default is set.	Missing values are not allowed for boolean data.
Error	A load error generates and the point is set to False.	Load errors are reported in the Load Summary Window.

Error Values

Load Error Data Type	Result
Floating data type	The sample is set to missing. That is, there is no entry for this sample.
String data type	The sample is set to missing. That is, there is no entry for this sample. An error is unlikely for a string field because there is no data type conversion involved.
Integer data type	The sample value is set to 0 (zero).
Boolean data type	The sample value is set to false.