| Name | Range | Description | Optional? |
|---|---|---|---|
| COORDINATE_SYSTEM_DEF | any string | The name of the coordinate system being defined.May be used to identify the coordinate system of a reader or writer, or as an argument to @Reproject or _COORDINATE_SYSTEM. | 没有 |
| DT_NAME | 看到基准。 | 用于投影的数据关键。任一基准或椭圆体必须为每个坐标系统来说明。 当特征标记与这种类型的坐标系统被重新投影，无基准变换被应用。 |
是, unless EL_NAME is specified |
| DESC_NM | 任何字符串，63个字符最大 | A descriptive name of the coordinate system. | 是 |
| EL_NAME | 看到椭球。 | 椭圆键名的cartographically基准坐标系。坐标系是cartographically参照本规范命名的，当且仅当，省略了基准键名称规范的椭球。如果提供两个DT_NAME和EL_NAME规格，EL_NAME将被忽略。 当特征标记与这种类型的坐标系统被重新投影，无基准变换被应用。 |
是, unless DT_NAME is specified |
| GROUP |
|
是 | |
| MAX_LNG | The maximum longitude of the useful range of the coordinate system.The value is given in degrees relative to Greenwich.Positive values indicate east longitude, while negative values indicate west longitude.Its value should be normalized between -360 and +360 and, when used, must be algebraically greater than the MIN_LNG parameter. | 是 | |
| MIN_LNG | The minimum longitude of the useful range of the coordinate system.The value is given in degrees relative to Greenwich.Positive values indicate east longitude, while negative values indicate west longitude.Its value should be normalized between -360 and +360 and, when used, must be algebraically less than the MAX_LNG parameter. | 是 | |
| MAX_LAT | The maximum latitude of the useful range of the coordinate system.The value is given in degrees relative to the equator.Positive values indicate north latitude while negative values indicate south latitude.Its value should be normalized between -90 and +90 and when used must be algebraically greater than the MIN_LAT parameter. | 是 | |
| MIN_LAT | The minimum latitude of the useful range of the coordinate system.The value is given in degrees relative to the equator.Positive values indicate north latitude while negative values indicate south latitude.Its value should be normalized between -90 and +90 and, when used, must be algebraically less than the MAX_LAT parameter. | 是 | |
| MAX_XX | The maximum X coordinate value of the useful range of the coordinate system.The value is given in system units.Its value must be algebraically greater than the MIN_XX parameter. | 是 | |
| MIN_XX | The minimum X coordinate value of the useful range of the coordinate system.The value is given in system units.Its value must be algebraically less than the MAX_XX parameter. | 是 | |
| MAX_YY | The maximum Y coordinate value of the useful range of the coordinate system.The value is given in system units.Its value must be algebraically greater than the MIN_YY parameter. | 是 | |
| MIN_YY | The minimum Y coordinate value of the useful range of the coordinate system.The value is given in system units.Its value must be algebraically less than the MAX_YY parameter. | 是 | |
| ORG_LAT | The origin latitude of the coordinate system.This value is specified in degrees relative to the equator.Use positive numbers for north latitude, negative numbers for south latitude. | 是 | |
| ORG_LNG | The origin longitude of the coordinate system.This value is specified in degrees and is always relative to the Greenwich prime meridian.Use positive numbers for east longitude, negative numbers for west longitude. | 是 | |
| PARM1 thru PARM24 | Depends on the projection system – see投影类型。 | The value of up to 24 parameters that are specific to the particular projection in use.The use of these items varies from one projection to another.The value is always a real number.Where a longitude is specified, it must be given in degrees, relative to Greenwich, where west longitude and south latitude are negative.Where a latitude is expected, it must be given in degrees relative to the equator where north latitude is positive and south latitude is negative.When an azimuth is specified, it must be given in degrees east of north (that is, west of north would be negative). | 没有 |
| PROJ | 看到投影类型。 | The type of map projection used for this definition.This name must come from the Projection Types table and it determines which other parameters may be specified.The parameters used by each projection type are linked to the Projection Types table. | 没有 |
| QUAD | -4..4 | The quadrant of the Cartesian coordinates produced by the coordinate system.看到象限。Zero or 1 indicates the normal right-handed Cartesian system where X increases to the east, and Y increases to the north.象限s are numbered counterclockwise;therefore, a value of 2 specifies a Cartesian system where X increases to the west, while Y increases north.A value of 3 indicates that X increases to the west and Y increases to the south.A value of 4 indicates that X increases to the east and Y increases to the south.A negative value causes the axes to be swapped after the appropriate quadrant is applied.A value of 1 is assumed if this specification is absent. | 是 |
| SCL_RED | The scale reduction that may apply to a coordinate system.该值由不支持此功能的许多预测忽略。的值可以被指定为一个十进制数（例如，0.9996），或者作为比（例如，1：2500）。1.0或更大的值是不寻常的，但被接受。 | 是 | |
| 资源 | 任何字符串，63个字符最大 | 该人或机构提供的定义。 | 是 |
| 单元 | 看到坐标单位支持。 | 用于测量坐标系中的坐标单位的名称。 | 没有 |
| X_OFF | 坐标系的东移的价值。假定值为0.0，如果没有指定，则。 | 是 | |
| Y_OFF | 坐标系的北移假定值。假定值为0.0，如果没有指定，则。 | 是 | |
| ZERO_X | 任何非负数 | 这是最低的X值要考虑非零。X坐标值，其绝对值小于此处指定的值将被转换为硬零。这是用来抑制坐标输出如4.3472E-07，其可以是在某些应用中的价值。假定值为0.0，如果没有指定，则。 | 是 |
| ZERO_Y | 任何非负数 | 最小Y值，其将被认为是非零的。Y坐标值的绝对值小于此处指定将被转换为硬零值。这是用来抑制坐标输出如4.3472E-07，其可以是在某些应用中的价值。假定值为0.0，如果没有指定，则。 | 是 |