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sardanaattribute

This module is part of the Python Sardana libray. It defines the base classes for Sardana attributes

Classes

SardanaAttribute

Inheritance diagram of SardanaAttribute

class SardanaAttribute(obj, name=None, initial_value=None, **kwargs)[source]

Class representing an atomic attribute like position of a motor or a counter value

has_value()[source]

Determines if the attribute’s read value has been read at least once in the lifetime of the attribute.

Returns:True if the attribute has a read value stored or False otherwise
Return type:bool
has_write_value()[source]

Determines if the attribute’s write value has been read at least once in the lifetime of the attribute.

Returns:True if the attribute has a write value stored or False otherwise
Return type:bool
get_obj()[source]

Returns the object which owns this attribute

Returns:the object which owns this attribute
Return type:obj
in_error()[source]

Determines if this attribute is in error state.

Returns:True if the attribute is in error state or False otherwise
Return type:bool
set_value(value, exc_info=None, timestamp=None, propagate=1)[source]

Sets the current read value and propagates the event (if propagate > 0).

Parameters:
  • value (obj or SardanaValue) – the new read value for this attribute. If a SardanaValue is given, exc_info and timestamp are ignored (if given)
  • exc_info (tuple<3> or None) – exception information as returned by sys.exc_info() [default: None, meaning no exception]
  • timestamp (float or None) – timestamp of attribute readout [default: None, meaning create a ‘now’ timestamp]
  • propagate (int) – 0 for not propagating, 1 to propagate, 2 propagate with priority
get_value()[source]

Returns the last read value for this attribute.

Returns:the last read value for this attribute
Return type:obj
Raises :Exception if no read value has been set yet
get_value_obj()[source]

Returns the last read value for this attribute.

Returns:the last read value for this attribute
Return type:SardanaValue
Raises :Exception if no read value has been set yet
set_write_value(w_value, timestamp=None, propagate=1)[source]

Sets the current write value.

Parameters:
  • value (obj or SardanaValue) – the new write value for this attribute. If a SardanaValue is given, timestamp is ignored (if given)
  • timestamp (float or None) – timestamp of attribute write [default: None, meaning create a ‘now’ timestamp]
  • propagate (int) – 0 for not propagating, 1 to propagate, 2 propagate with priority
get_write_value()[source]

Returns the last write value for this attribute.

Returns:the last write value for this attribute or None if value has not been written yet
Return type:obj
get_write_value_obj()[source]

Returns the last write value object for this attribute.

Returns:the last write value for this attribute or None if value has not been written yet
Return type:SardanaValue
get_exc_info()[source]

Returns the exception information (like sys.exc_info()) about last attribute readout or None if last read did not generate an exception.

Returns:exception information or None
Return type:tuple<3> or None
accepts(propagate)[source]
get_timestamp()[source]

Returns the timestamp of the last readout or None if the attribute has never been read before

Returns:timestamp of the last readout or None
Return type:float or None
get_write_timestamp()[source]

Returns the timestamp of the last write or None if the attribute has never been written before

Returns:timestamp of the last write or None
Return type:float or None
fire_write_event(propagate=1)[source]

Fires an event to the listeners of the object which owns this attribute.

Parameters:propagate (int) – 0 for not propagating, 1 to propagate, 2 propagate with priority
fire_read_event(propagate=1)[source]

Fires an event to the listeners of the object which owns this attribute.

Parameters:propagate (int) – 0 for not propagating, 1 to propagate, 2 propagate with priority
obj

Returns the object which owns this attribute

Returns:the object which owns this attribute
Return type:obj
value_obj

Returns the last read value for this attribute.

Returns:the last read value for this attribute
Return type:SardanaValue
Raises :Exception if no read value has been set yet
write_value_obj

Returns the last write value object for this attribute.

Returns:the last write value for this attribute or None if value has not been written yet
Return type:SardanaValue
value

Returns the last read value for this attribute.

Returns:the last read value for this attribute
Return type:obj
Raises :Exception if no read value has been set yet
w_value

Returns the last write value for this attribute.

Returns:the last write value for this attribute or None if value has not been written yet
Return type:obj
timestamp

the read timestamp

w_timestamp

the write timestamp

error

Determines if this attribute is in error state.

Returns:True if the attribute is in error state or False otherwise
Return type:bool
exc_info

Returns the exception information (like sys.exc_info()) about last attribute readout or None if last read did not generate an exception.

Returns:exception information or None
Return type:tuple<3> or None
add_listener(listener)

Adds a new listener for this object.

Parameters:listener – a listener
fire_event(event_type, event_value, listeners=None)
flush_queue()
has_listeners()

Returns True if anybody is listening to events from this object

Returns:True is at least one listener is listening or False otherwise
queue_event(event_type, event_value, listeners=None)
remove_listener(listener)

Removes an existing listener for this object.

Parameters:listener – the listener to be removed
Returns:True is succeeded or False otherwise

SardanaSoftwareAttribute

Inheritance diagram of SardanaSoftwareAttribute

class SardanaSoftwareAttribute(obj, name=None, initial_value=None, **kwargs)[source]

Class representing a software attribute. The difference between this and SardanaAttribute is that, because it is a pure software attribute, there is no difference ever between the read and write values.

get_value()

Returns the last read value for this attribute.

Returns:the last read value for this attribute
Return type:obj
Raises :Exception if no read value has been set yet
set_value(value, exc_info=None, timestamp=None, propagate=1)[source]

Sets the current read value and propagates the event (if propagate > 0).

Parameters:
  • value (obj) – the new read value for this attribute
  • exc_info (tuple<3> or None) – exception information as returned by sys.exc_info() [default: None, meaning no exception]
  • timestamp (float or None) – timestamp of attribute readout [default: None, meaning create a ‘now’ timestamp]
  • propagate (int) – 0 for not propagating, 1 to propagate, 2 propagate with priority
value

Returns the last read value for this attribute.

Returns:the last read value for this attribute
Return type:obj
Raises :Exception if no read value has been set yet
accepts(propagate)
add_listener(listener)

Adds a new listener for this object.

Parameters:listener – a listener
error

Determines if this attribute is in error state.

Returns:True if the attribute is in error state or False otherwise
Return type:bool
exc_info

Returns the exception information (like sys.exc_info()) about last attribute readout or None if last read did not generate an exception.

Returns:exception information or None
Return type:tuple<3> or None
fire_event(event_type, event_value, listeners=None)
fire_read_event(propagate=1)

Fires an event to the listeners of the object which owns this attribute.

Parameters:propagate (int) – 0 for not propagating, 1 to propagate, 2 propagate with priority
fire_write_event(propagate=1)

Fires an event to the listeners of the object which owns this attribute.

Parameters:propagate (int) – 0 for not propagating, 1 to propagate, 2 propagate with priority
flush_queue()
get_exc_info()

Returns the exception information (like sys.exc_info()) about last attribute readout or None if last read did not generate an exception.

Returns:exception information or None
Return type:tuple<3> or None
get_obj()

Returns the object which owns this attribute

Returns:the object which owns this attribute
Return type:obj
get_timestamp()

Returns the timestamp of the last readout or None if the attribute has never been read before

Returns:timestamp of the last readout or None
Return type:float or None
get_value_obj()

Returns the last read value for this attribute.

Returns:the last read value for this attribute
Return type:SardanaValue
Raises :Exception if no read value has been set yet
get_write_timestamp()

Returns the timestamp of the last write or None if the attribute has never been written before

Returns:timestamp of the last write or None
Return type:float or None
get_write_value()

Returns the last write value for this attribute.

Returns:the last write value for this attribute or None if value has not been written yet
Return type:obj
get_write_value_obj()

Returns the last write value object for this attribute.

Returns:the last write value for this attribute or None if value has not been written yet
Return type:SardanaValue
has_listeners()

Returns True if anybody is listening to events from this object

Returns:True is at least one listener is listening or False otherwise
has_value()

Determines if the attribute’s read value has been read at least once in the lifetime of the attribute.

Returns:True if the attribute has a read value stored or False otherwise
Return type:bool
has_write_value()

Determines if the attribute’s write value has been read at least once in the lifetime of the attribute.

Returns:True if the attribute has a write value stored or False otherwise
Return type:bool
in_error()

Determines if this attribute is in error state.

Returns:True if the attribute is in error state or False otherwise
Return type:bool
obj

Returns the object which owns this attribute

Returns:the object which owns this attribute
Return type:obj
queue_event(event_type, event_value, listeners=None)
remove_listener(listener)

Removes an existing listener for this object.

Parameters:listener – the listener to be removed
Returns:True is succeeded or False otherwise
set_write_value(w_value, timestamp=None, propagate=1)

Sets the current write value.

Parameters:
  • value (obj or SardanaValue) – the new write value for this attribute. If a SardanaValue is given, timestamp is ignored (if given)
  • timestamp (float or None) – timestamp of attribute write [default: None, meaning create a ‘now’ timestamp]
  • propagate (int) – 0 for not propagating, 1 to propagate, 2 propagate with priority
timestamp

the read timestamp

value_obj

Returns the last read value for this attribute.

Returns:the last read value for this attribute
Return type:SardanaValue
Raises :Exception if no read value has been set yet
w_timestamp

the write timestamp

w_value

Returns the last write value for this attribute.

Returns:the last write value for this attribute or None if value has not been written yet
Return type:obj
write_value_obj

Returns the last write value object for this attribute.

Returns:the last write value for this attribute or None if value has not been written yet
Return type:SardanaValue

ScalarNumberAttribute

Inheritance diagram of ScalarNumberAttribute

class ScalarNumberAttribute(*args, **kwargs)[source]

A SardanaAttribute specialized for numbers

accepts(propagate)
add_listener(listener)

Adds a new listener for this object.

Parameters:listener – a listener
error

Determines if this attribute is in error state.

Returns:True if the attribute is in error state or False otherwise
Return type:bool
exc_info

Returns the exception information (like sys.exc_info()) about last attribute readout or None if last read did not generate an exception.

Returns:exception information or None
Return type:tuple<3> or None
fire_event(event_type, event_value, listeners=None)
fire_read_event(propagate=1)

Fires an event to the listeners of the object which owns this attribute.

Parameters:propagate (int) – 0 for not propagating, 1 to propagate, 2 propagate with priority
fire_write_event(propagate=1)

Fires an event to the listeners of the object which owns this attribute.

Parameters:propagate (int) – 0 for not propagating, 1 to propagate, 2 propagate with priority
flush_queue()
get_exc_info()

Returns the exception information (like sys.exc_info()) about last attribute readout or None if last read did not generate an exception.

Returns:exception information or None
Return type:tuple<3> or None
get_obj()

Returns the object which owns this attribute

Returns:the object which owns this attribute
Return type:obj
get_timestamp()

Returns the timestamp of the last readout or None if the attribute has never been read before

Returns:timestamp of the last readout or None
Return type:float or None
get_value()

Returns the last read value for this attribute.

Returns:the last read value for this attribute
Return type:obj
Raises :Exception if no read value has been set yet
get_value_obj()

Returns the last read value for this attribute.

Returns:the last read value for this attribute
Return type:SardanaValue
Raises :Exception if no read value has been set yet
get_write_timestamp()

Returns the timestamp of the last write or None if the attribute has never been written before

Returns:timestamp of the last write or None
Return type:float or None
get_write_value()

Returns the last write value for this attribute.

Returns:the last write value for this attribute or None if value has not been written yet
Return type:obj
get_write_value_obj()

Returns the last write value object for this attribute.

Returns:the last write value for this attribute or None if value has not been written yet
Return type:SardanaValue
has_listeners()

Returns True if anybody is listening to events from this object

Returns:True is at least one listener is listening or False otherwise
has_value()

Determines if the attribute’s read value has been read at least once in the lifetime of the attribute.

Returns:True if the attribute has a read value stored or False otherwise
Return type:bool
has_write_value()

Determines if the attribute’s write value has been read at least once in the lifetime of the attribute.

Returns:True if the attribute has a write value stored or False otherwise
Return type:bool
in_error()

Determines if this attribute is in error state.

Returns:True if the attribute is in error state or False otherwise
Return type:bool
obj

Returns the object which owns this attribute

Returns:the object which owns this attribute
Return type:obj
queue_event(event_type, event_value, listeners=None)
remove_listener(listener)

Removes an existing listener for this object.

Parameters:listener – the listener to be removed
Returns:True is succeeded or False otherwise
set_value(value, exc_info=None, timestamp=None, propagate=1)

Sets the current read value and propagates the event (if propagate > 0).

Parameters:
  • value (obj or SardanaValue) – the new read value for this attribute. If a SardanaValue is given, exc_info and timestamp are ignored (if given)
  • exc_info (tuple<3> or None) – exception information as returned by sys.exc_info() [default: None, meaning no exception]
  • timestamp (float or None) – timestamp of attribute readout [default: None, meaning create a ‘now’ timestamp]
  • propagate (int) – 0 for not propagating, 1 to propagate, 2 propagate with priority
set_write_value(w_value, timestamp=None, propagate=1)

Sets the current write value.

Parameters:
  • value (obj or SardanaValue) – the new write value for this attribute. If a SardanaValue is given, timestamp is ignored (if given)
  • timestamp (float or None) – timestamp of attribute write [default: None, meaning create a ‘now’ timestamp]
  • propagate (int) – 0 for not propagating, 1 to propagate, 2 propagate with priority
timestamp

the read timestamp

value

Returns the last read value for this attribute.

Returns:the last read value for this attribute
Return type:obj
Raises :Exception if no read value has been set yet
value_obj

Returns the last read value for this attribute.

Returns:the last read value for this attribute
Return type:SardanaValue
Raises :Exception if no read value has been set yet
w_timestamp

the write timestamp

w_value

Returns the last write value for this attribute.

Returns:the last write value for this attribute or None if value has not been written yet
Return type:obj
write_value_obj

Returns the last write value object for this attribute.

Returns:the last write value for this attribute or None if value has not been written yet
Return type:SardanaValue

SardanaAttributeConfiguration

Inheritance diagram of SardanaAttributeConfiguration

class SardanaAttributeConfiguration[source]

Storage class for SardanaAttribute information (like ranges)

NoRange = (-inf, inf)