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Cell Type
A cell type denotes the possible ways a cell's value can be represented within a Map or Categorical Map.
| Cell Type | Domain | Cell Size | Signed | Minimum Value | Maximum Value | Default Null |
|---|---|---|---|---|---|---|
| 1 Bit Integer | Integer (whole numbers only) | 1 bit | No (non-negative values only) | 0 | 1 | 0 |
| Signed 8 Bit Integer | 1 byte | Yes (positive and negative values) | -128 | 127 | -128 | |
| Unsigned 8 Bit Integer | 1 byte | No (non-negative values only) | 0 | 255 | 0 | |
| Signed 16 Bit Integer | 2 bytes | Yes (positive and negative values) | -32768 | 32767 | -32768 | |
| Unsigned 16 Bit Integer | 2 bytes | No (non-negative values only) | 0 | 65535 | 0 | |
| Signed 32 Bit Integer | 4 bytes | Yes (positive and negative values) | -2147483648 | 2147483647 | -2147483648 | |
| Unsigned 32 Bit Integer | 4 bytes | No (non-negative values only) | 0 | 4294967295 | 0 | |
| IEEE 754 32 Bit Real | Real (fractional and whole numbers) | 4 bytes | Yes (positive and negative values) | -3.4028235*1038 | 3.4028235*1038 | -9999 |
| IEEE 754 64 Bit Real | Real (fractional and whole numbers) | 8 bytes | Yes (positive and negative values) | -2.2250738585072014*10308 | 2.2250738585072014*10308 | -9999 |
Both real cell types have limited precision: IEEE 754 32 Bit Real usually preserves only about 7 significant digits, and IEEE 754 64 Bit Real about 16.
A cell type value can also be created from integral values, such as Integer Value, Positive Integer Value, and Non Negative Integer Value, and from real values, such as Real Value. The mapping between numeric values and their corresponding cell type values is shown below:
| Numeric Value | Cell Type |
|---|---|
| 0 | 1 Bit Integer |
| 1 | Signed 8 Bit Integer |
| 2 | Unsigned 8 Bit Integer |
| 3 | Signed 16 Bit Integer |
| 4 | Unsigned 16 Bit Integer |
| 5 | Signed 32 Bit Integer |
| 6 | Unsigned 32 Bit Integer |
| 7 | IEEE 754 32 Bit Real |
| 8 | IEEE 754 64 Bit Real |
Defining a map with the 1 Bit Integer cell type saves memory, but at a significant cost to performance. Conversely, IEEE 754 64 Bit Real uses far more memory than any other cell type.
GUI Editor
EGO Script
A cell type constant can be represented in EGO Script — see Constants — using the following syntax:
| Cell Type | Representation |
|---|---|
| 1 Bit Integer | .uint1 |
| Signed 8 Bit Integer | .int8 |
| Unsigned 8 Bit Integer | .uint8 |
| Signed 16 Bit Integer | .int16 |
| Unsigned 16 Bit Integer | .uint16 |
| Signed 32 Bit Integer | .int32 |
| Unsigned 32 Bit Integer | .uint32 |
| IEEE 754 32 Bit Real | .float32 |
| IEEE 754 64 Bit Real | .float64 |
Automatic Conversions
- Converted from: Real Value Type, Non Negative Integer Value Type, Positive Integer Value Type, and Integer Value Type — using the numeric-to-cell-type mapping shown above.
- Converted to: Real Value Type, Non Negative Integer Value Type, Positive Integer Value Type, and Integer Value Type.
See Type System for the complete conversion reference across all types — this page's conversions are confirmed there exactly as listed, with no additional failure or information-loss behavior recorded.