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Publication date: 11/10/2021

Structure of a Data Table

A data table has fixed rows and columns, while a spreadsheet is cell based. In a spreadsheet, data, headings, or formulas can be placed in any cell. In a data table, the structure organizes data for analysis. This structure is used by JMP analysis and graphing platforms.

Column Headings

Column names are column headings.


Columns contain data and are assigned one data type. Basic columns are either numeric or character. If a column contains both character and numeric data, the entire column’s data type is character, and the numbers are treated as character data. JMP also has specialized column types for capturing things such as images. JMP uses the column’s data type to determine analysis options and results. For more information about data types, see Understand Modeling Types.


Rows contain observations. If there is no observation for a row, that cell is left empty. In JMP a dot signifies a missing numeric value, and a blank signifies a missing character value,

For more information about JMP data tables, see Understand Data Tables. For more information about JMP column properties, see Column Properties in JMP in the Using JMP book.

JMP data tables cannot be arranged in a workbook such as in Excel. Each JMP data table is a separate file and appears in its own window. To combine multiple tables, see Reshape Your Data in the Using JMP book. For organizing JMP tables and output see Save and Run Scripts.

Tip: To use data from two or more tables in a single analysis, use Virtual Join. For more information, see Virtually Join Data Tables in the Using JMP book.

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