twisted.positioning.base.PositionError(FancyEqMixin, object)
class documentationtwisted.positioning.base
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Position error information.
Instance Variable | pdop | The position dilution of precision. None
if unknown. (type: float or None ) |
Instance Variable | hdop | The horizontal dilution of precision. None
if unknown. (type: float or None ) |
Instance Variable | vdop | The vertical dilution of precision. None
if unknown. (type: float or None ) |
Method | __init__ | Initializes a positioning error object. |
Method | __repr__ | Returns a string representation of positioning information object. |
Class Variable | _ALLOWABLE_THRESHOLD | The maximum allowable difference between PDOP and the geometric mean of
VDOP and HDOP. That difference is supposed to be zero, but can be non-zero
because of rounding error and limited reporting precision. You should never
have to change this value. (type: float ) |
Class Variable | _DOP_EXPRESSIONS | A mapping of DOP types (C[hvp]dop) to a list of callables that take self
and return that DOP type, or raise TypeError . This allows a
DOP value to either be returned directly if it's know, or computed from
other DOP types if it isn't. (type: dict of str to callables) |
Method | _testDilutionOfPositionInvariant | Tests if this positioning error object satisfies the dilution of
position invariant (PDOP = (HDOP**2 + VDOP**2)*.5), unless the
self._testInvariant instance variable is
False . |
Method | _getDOP | Gets a particular dilution of position value. |
Method | _setDOP | Sets a particular dilution of position value. |
Inherited from FancyEqMixin:
Method | __eq__ | Undocumented |
Method | __ne__ | Undocumented |
float
)
TypeError
. This allows a
DOP value to either be returned directly if it's know, or computed from
other DOP types if it isn't. (type: dict
of str
to callables)
Initializes a positioning error object.
Parameters | pdop | The position dilution of precision. None
if unknown. (type: float or None ) |
hdop | The horizontal dilution of precision. None
if unknown. (type: float or None ) | |
vdop | The vertical dilution of precision. None
if unknown. (type: float or None ) | |
testInvariant | Flag to test if the DOP invariant is valid or not. If True ,
the invariant (PDOP = (HDOP**2 + VDOP**2)*.5) is checked at every mutation.
By default, this is false, because the vast majority of DOP-providing
devices ignore this invariant. (type: c{bool}) |
Tests if this positioning error object satisfies the dilution of
position invariant (PDOP = (HDOP**2 + VDOP**2)*.5), unless the
self._testInvariant
instance variable is
False
.
Returns | None
if the invariant was not satisfied or not tested. | |
Raises | ValueError | Raised if the invariant was tested but not satisfied. |
Sets a particular dilution of position value.
Parameters | dopType | The type of dilution of position to set. One of ('pdop', 'hdop', 'vdop'). (type: str ) |
value | The value to set the dilution of position type to. (type: float
If this position error tests dilution of precision invariants, it will
be checked. If the invariant is not satisfied, the assignment will be
undone and |
Returns a string representation of positioning information object.
Returns | The string representation. (type: str ) |