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Cell Type

A cell type denotes several possible cell representations in a Map or Categorical Map.

Cell Type Domain Cell Size Signed Minimum Value Maximum Value Default Null
1 Bit Integer Integer 1) 1 bit No 0 1 0
Signed 8 Bit Integer 1 byte Yes 2) -128 127 -128
Unsigned 8 Bit Integer 1 byte No 3) 0 255 0
Signed 16 Bit Integer 2 bytes Yes 4) -32768 32767 -32768
Unsigned 16 Bit Integer 2 bytes No 5) 0 65535 0
Signed 32 Bit Integer 4 bytes Yes 6) -2147483648 2147483647 -2147483648
Unsigned 32 Bit Integer 4 bytes Yes 7) 0 4294967295 0
IEEE 754 32 Bit Real8) Real 9) 4 bytes Yes 10) -3.4028235*1038 3.4028235*1038 -9999

A cell type value can also be created from integral values, like Integer, Positive Integer, Non Negative Integer etc, and from real values, like Double. The mapping of numeric values and their corresponding cell type values can be seen 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

It is worth noting that the definition of maps with cell type “1 Bit Integer” helps saving memory, but it also has a huge negative impact in performance.

GUI Editor

Graphical representation of the cell type editor

EGO Script

A cell type constant can be represented in a EGO Script 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

Automatic Conversions

  • Converted to: None.
1)
can represent only integer values
2) , 4) , 6) , 10)
can represent positive and negative values
3) , 5) , 7)
can represent only positive values
8)
A value represented in this format usually have only 7 significant digits
9)
can represent fractional and integer values