How do you get access to the dictionary under traits.api.Dict()? - python

Here is an example of failure from a shell.
>>> from traits.api import Dict
>>> d=Dict()
>>> d['Foo']='BAR'
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: 'Dict' object does not support item assignment
I have been searching all over the web, and there is no indication of how to use Dict.
I am trying to write a simple app that displays the contents of a python dictionary. This link (Defining view elements from dictionary elements in TraitsUI) was moderately helpful except for the fact that the dictionary gets updated on some poll_interval and if I use the solution there (wrapping a normal python dict in a class derived from HasTraits) the display does not update when the underlying dictionary gets updated.
Here are the relevant parts of what I have right now. The last class can pretty much be ignored, the only reason I included it is to help understand how I intend to use the Dict.
pyNetObjDisplay.run_ext() gets called once per loop from the base classes run() method
class DictContainer(HasTraits):
_dict = {}
def __getattr__(self, key):
return self._dict[key]
def __getitem__(self, key):
return self._dict[key]
def __setitem__(self, key, value):
self._dict[key] = value
def __delitem__(self, key, value):
del self._dict[key]
def __str__(self):
return self._dict.__str__()
def __repr__(self):
return self._dict.__repr__()
def has_key(self, key):
return self._dict.has_key(key)
class displayWindow(HasTraits):
_remote_data = Instance(DictContainer)
_messages = Str('', desc='Field to display messages to the user.', label='Messages', multi_line=True)
def __remote_data_default(self):
tempDict = DictContainer()
tempDict._dict = Dict
#tempDict['FOO'] = 'BAR'
sys.stderr.write('SETTING DEFAULT DICTIONARY:\t%s\n' % tempDict)
return tempDict
def __messages_default(self):
tempStr = Str()
tempStr = ''
return tempStr
def traits_view(self):
return View(
Item('object._remote_data', editor=ValueEditor()),
Item('object._messages'),
resizable=True
)
class pyNetObjDisplay(pyNetObject.pyNetObjPubClient):
'''A derived pyNetObjPubClient that stores remote data in a dictionary and displays it using traitsui.'''
def __init__(self, hostname='localhost', port=54322, service='pyNetObject', poll_int=10.0):
self._display = displayWindow()
self.poll_int = poll_int
super(pyNetObjDisplay, self).__init__(hostname, port, service)
self._ui_running = False
self._ui_pid = 0
### For Testing Only, REMOVE THESE LINES ###
self.connect()
self.ns_subscribe(service, 'FOO', poll_int)
self.ns_subscribe(service, 'BAR', poll_int)
self.ns_subscribe(service, 'BAZ', poll_int)
############################################
def run_ext(self):
if not self._ui_running:
self._ui_running = True
self._ui_pid = os.fork()
if not self._ui_pid:
time.sleep(1.25*self.poll_int)
self._display.configure_traits()
for ((service, namespace, key), value) in self._object_buffer:
sys.stderr.write('TEST:\t' + str(self._display._remote_data) + '\n')
if not self._display._remote_data.has_key(service):
self._display._remote_data[service] = {}
if not self._display._remote_data[service].has_key(namespace):
#self._remote_data[service][namespace] = {}
self._display._remote_data[service][namespace] = {}
self._display._remote_data[service][namespace][key] = value
msg = 'Got Published ((service, namespace, key), value) pair:\t((%s, %s, %s), %s)\n' % (service, namespace, key, value)
sys.stderr.write(msg)
self._display._messages += msg
sys.stderr.write('REMOTE DATA:\n' + str(self._display._remote_data)
self._object_buffer = []

I think your basic problem has to do with notification issues for traits that live outside the model object, and not with "how to access those objects" per se [edit: actually no this is not your problem at all! But it is what I thought you were trying to do when I read your question with my biased mentality towards problems I have seen before and in any case my suggested solution will still work]. I have run into this sort of problem recently because of how I decided to design my program (with code describing a GUI separated modularly from the very complex sets of data that it can contain). You may have found my other questions, as you found the first one.
Having lots of data live in a complex data hierarchy away from the GUI is not the design that traitsui has in mind for your application and it causes all kinds of problems with notifications. Having a flatter design where GUI information is integrated into the different parts of your program more directly is the design solution.
I think that various workarounds might be possible for this in general (I have used some for instance in enabled_when listening outside model object) that don't involve dictionaries. I'm not sure what the most design friendly solution to your problem with dictionaries is, but one thing that works and doesn't interfere a lot with your design (but it is still a "somewhat annoying" solution) is to make everything in a dictionary be a HasTraits and thus tag it as listenable. Like so:
from traits.api import *
from traitsui.api import *
from traitsui.ui_editors.array_view_editor import ArrayViewEditor
import numpy as np
class DContainer(HasTraits):
_dict=Dict
def __getattr__(self, k):
if k in self._dict:
return self._dict[k]
class DItem(HasTraits):
_item=Any
def __init__(self,item):
super(DItem,self).__init__()
self._item=item
def setitem(self,val):
self._item=val
def getitem(self):
return self._item
def traits_view(self):
return View(Item('_item',editor=ArrayViewEditor()))
class LargeApplication(HasTraits):
d=Instance(DContainer)
stupid_listener=Any
bn=Button('CLICKME')
def _d_default(self):
d=DContainer()
d._dict={'a_stat':DItem(np.random.random((10,1))),
'b_stat':DItem(np.random.random((10,10)))}
return d
def traits_view(self):
v=View(
Item('object.d.a_stat',editor=InstanceEditor(),style='custom'),
Item('bn'),
height=500,width=500)
return v
def _bn_fired(self):
self.d.a_stat.setitem(np.random.random((10,1)))
LargeApplication().configure_traits()

Okay, I found the answer (kindof) in this question: Traits List not reporting items added or removed
when including Dict or List objects as attributes in a class one should NOT do it this way:
class Foo(HasTraits):
def __init__(self):
### This will not work as expected!
self.bar = Dict(desc='Description.', label='Name', value={})
Instead do this:
class Foo(HasTraits):
def __init__(self):
self.add_trait('bar', Dict(desc='Description.', label='Name', value={}) )
Now the following will work:
>>> f = Foo()
>>> f.bar['baz']='boo'
>>> f.bar['baz']
'boo'
Unfortunately for some reason the GUI generated with configure_traits() does not update it's view when the underlying data changes. Here is some test code that demonstrates the problem:
import os
import time
import sys
from traits.api import HasTraits, Str, Dict
from traitsui.api import View, Item, ValueEditor
class displayWindow(HasTraits):
def __init__(self, **traits):
super(displayWindow, self).__init__(**traits)
self.add_trait('_remote_data', Dict(desc='Dictionary to store remote data in.', label='Data', value={}) )
self.add_trait('_messages', Str(desc='Field to display messages to the user.', label='Messages', multi_line=True, value='') )
def traits_view(self):
return View(
Item('object._remote_data', editor=ValueEditor()),
Item('object._messages'),
resizable=True
)
class testObj(object):
def __init__(self):
super(testObj, self).__init__()
self._display = displayWindow()
self._ui_pid = 0
def run(self):
### Run the GUI in the background
self._ui_pid = os.fork()
if not self._ui_pid:
self._display.configure_traits()
i = 0
while True:
self._display._remote_data[str(i)] = i
msg = 'Added (key,value):\t("%s", %s)\n' % (str(i), i, )
self._display._messages += msg
sys.stderr.write(msg)
time.sleep(5.0)
i+=1
if __name__ == '__main__':
f = testObj()
f.run()

Related

How to get the clock arguement of event.post(clock, data, duration) in a python device?

I cannot find an example in the Simics documentation on how the clock object is obtained so that we can use it as an argument in the post() method.
I suspect that either
an attribute can be used to get the clock or
in the ConfObject class scope we get the clock using SIM_object_clock()
I created a new module using bin\project-setup --py-device event-py
I have defined two methods in the ConfObject class scope called clock_set and clock_get.
I wanted to use these methods so that I can set/get the clock object to use in the post method.
The post() method fails when reading the device registers in the vacuum machine.
import pyobj
# Tie code to specific API, simplifying upgrade to new major version
import simics_6_api as simics
class event_py(pyobj.ConfObject):
"""This is the long-winded documentation for this Simics class.
It can be as long as you want."""
_class_desc = "one-line doc for the class"
_do_not_init = object()
def _initialize(self):
super()._initialize()
def _info(self):
return []
def _status(self):
return [("Registers", [("value", self.value.val)])]
def getter(self):
return self
# In my mind, clock_set is supposed to set the clock object. That way we can use
# it in post()
def clock_set(self):
self.clock = simics.SIM_object_clock(self)
def clock_get(self):
return self.clock(self):
class value(pyobj.SimpleAttribute(0, 'i')):
"""The <i>value</i> register."""
class ev1(pyobj.Event):
def callback(self, data):
return 'ev1 with %s' % data
class regs(pyobj.Port):
class io_memory(pyobj.Interface):
def operation(self, mop, info):
offset = (simics.SIM_get_mem_op_physical_address(mop)
+ info.start - info.base)
size = simics.SIM_get_mem_op_size(mop)
if offset == 0x00 and size == 1:
if simics.SIM_mem_op_is_read(mop):
val = self._up._up.value.val
simics.SIM_set_mem_op_value_le(mop, val)
# POST HERE AS TEST self._up._up.ev1.post(clock, val, seconds = 1)
else:
val = simics.SIM_get_mem_op_value_le(mop)
self._up._up.value.val = val
return simics.Sim_PE_No_Exception
else:
return simics.Sim_PE_IO_Error
You mention using the vacuum example machine and within its script you see that sdp->queue will point to timer. So SIM_object_clock(sdp) would return timer.
Simics is using queue attribute in all conf-objects to reference their clock individually, though other implementations are used too.
BR
Simon
#IAmIntel

Elegant way in Python to map string content to method calls

Given this example code where we have a series of log processors, I can't help feeling there ought to be a more pythonic/efficient way of deciding which log processor to use to process some data:
class Component1ErrorLogProcessor:
def process(logToProcess):
# Do something with the logs
pass
class Component2ErrorLogProcessor:
def process(logToProcess):
# Do something with the logs
pass
class LogProcessor:
def __init__(self):
self.component1 = Component1ErrorLogProcessor()
self.component2 = Component2ErrorLogProcessor()
def process_line(self, line, component):
if component == "Component1Log-" or component == "[Component1]":
self.component1.process_errors(line)
elif component == "Component2Log-" or component == "[Component2]":
self.component2.process_errors(line)
I'd personally use the idea of registry, so you map each class to component names.
There are a bunch of different ways to go about this, here's a quick example by using a base class:
class ComponentLogProcessor(object):
_Mapping = {}
#classmethod
def register(cls, *component_names):
for name in component_names:
cls._Mapping[name] = cls
#classmethod
def cls_from_component(cls, component):
return cls._Mapping[component]
class Component1ErrorLogProcessor(ComponentLogProcessor):
def process(logToProcess):
# Do something with the logs
pass
Component1ErrorLogProcessor.register('Component1Log-', '[Component1]')
class Component2ErrorLogProcessor(ComponentLogProcessor):
def process(logToProcess):
# Do something with the logs
pass
Component2ErrorLogProcessor.register('Component2Log-', '[Component2]')
class LogProcessor:
def process_line(self, line, component):
ComponentLogProcessor.cls_from_component(component).process_errors(line)

Python: Construct class (and variable names) through a function?

I recently started to work with Python's classes, since I need to work with it through the use of OTree, a Python framework used for online experiment.
In one file, I define the pages that I want to be created, using classes. So essentially, in the OTree system, each class corresponds to a new page. The thing is, all pages (so classes) are basically the same, at the exception to some two parameters, as shown in the following code:
class Task1(Page):
form_model = 'player'
form_fields = ['Envie_WordsList_Toy']
def is_displayed(self):
return self.round_number == self.participant.vars['task_rounds'][1]
def vars_for_template(player):
WordsList_Toy= Constants.WordsList_Toy.copy()
random.shuffle(WordsList_Toy)
return dict(
WordsList_Toy=WordsList_Toy
)
#staticmethod
def live_method(player, data):
player.WTP_WordsList_Toy = int(data)
def before_next_page(self):
self.participant.vars['Envie_WordsList_Toy'] = self.player.Envie_WordsList_Toy
self.participant.vars['WTP_WordsList_Toy'] = self.player.WTP_WordsList_Toy
So here, the only thing that would change would be the name of the class, as well as the suffix of the variable WordsList_ used throughout this code, which is Toy.
Naively, what I tried to do is to define a function that would take those two parameters, such as this:
def page_creation(Task_Number,name_type):
class Task+str(Task_Number)(Page):
form_model = 'player'
form_fields = ['Envie_WordsList_'+str(name_type)]
def is_displayed(self):
return self.round_number == self.participant.vars['task_rounds'][1]
def vars_for_template(player):
WordsList_+str(name_type) = Constants.WordsList+str(name_type).copy()
random.shuffle(WordsList_+str(name_type))
return dict(
WordsList_+str(name_type)=WordsList_+str(name_type)
)
#staticmethod
def live_method(player, data):
player.WTP_WordsList_+str(name_type) = int(data)
def before_next_page(self):
self.participant.vars['Envie_WordsList_+str(name_type)'] = self.player.Envie_WordsList_+str(name_type)
self.participant.vars['WTP_WordsList_+str(name_type)'] = self.player.WTP_WordsList_+str(name_type)
Obviously, it does not work since I have the feeling that it is not possible to construct variables (or classes identifier) this way. I just started to really work on Python some weeks ago, so some of its aspects might escape me still. Could you help me on this issue? Thank you.
You can generate dynamic classes using the type constructor:
MyClass = type("MyClass", (BaseClass1, BaseClass2), {"attr1": "value1", ...})
Thus, according to your case, that would be:
cls = type(f"Task{TaskNumber}", (Page, ), {"form_fields": [f"Envive_WordList_{name_type}"], ...})
Note that you still have to construct your common methods like __init__, is_displayed and so on, as inner functions of the class factory:
def class_factory(*args, **kwargs):
...
def is_displayed(self):
return self.round_number == self.participant.vars['task_rounds']
def vars_for_template(player):
...
# Classmethod wrapping is done below
def live_method(player, data):
...
cls = type(..., {
"is_displayed": is_displayed,
"vars_for_template": vars_for_template,
"live_method": classmethod(live_method),
...,
}
#classmethod could be used as a function - {"live_method": classmethod(my_method)}

Python class recording attributes without specifying self ?

I have a question regarding a Python class I use in Blender. Basically, I wonder how the class works because some attributes are recorded without me specifically writing self.value = something. Here's the code:
class DialogOperator(bpy.types.Operator):
bl_idname = "object.dialog_operator"
bl_label = "Save/Load animation"
saving = bpy.props.BoolProperty(name="Save ? Else load.")
path_to_anim = bpy.props.StringProperty(name="Path to folder")
anim_name = bpy.props.StringProperty(name="Animation name:")
# path_to_anim += "/home/mehdi/Blender/Scripts/"
def execute(self, context):
# print('This is execute with: Saving: {} Name:{}'.format(self.saving, self.path_to_anim))
if self.saving:
self.launch_save()
message = 'Animation {} saved at {}'.format(self.anim_name, self.path_to_anim)
else:
self.launch_load()
message = 'Animation {} loaded'.format(self.anim_name)
self.report({'INFO'}, message)
return {'FINISHED'}
def invoke(self, context, event):
wm = context.window_manager
return wm.invoke_props_dialog(self)
def launch_load(self):
full_path = self.path_to_anim + self.anim_name
target_armature = Humanoid(bpy.data.objects['Armature'])
load_all(full_path, target_armature, 'LastLoaded')
def launch_save(self):
full_path = self.path_to_anim + self.anim_name
source_armature = Humanoid(bpy.data.objects['Armature'])
curves = source_armature.get_curves()
save_all(curves, source_armature,full_path)
Now, how come saving, path_to_anim and anim_name are considered as attributes (I'm able to call them in execute() and launch()) even though I did not write self.saving = saving
Thanks !
This is because saving,path_to_anim and anim_name are class attributes. They are defined for the class and not for a particular instance. They are shared among the instances. Here is a link for further explanation class-instance-attributes-python

how to make a lot of parameters available to the entire system?

I have objects from various classes that work together to perform a certain task. The task requires a lot of parameters, provided by the user (through a configuration file). The parameters are used deep inside the system.
I have a choice of having the controller object read the configuration file, and then allocate the parameters as appropriate to the next layer of objects, and so on in each layer. But the only objects themselves know which parameters they need, so the controller object would need to learn a lot of detail about every other object.
The other choice is to bundle all the parameters into a collection, and pass the whole collection into every function call (equivalently, create a global object that stores them, and is accessible to everyone). This looks and feels ugly, and would cause a variety of minor technical issues (e.g., I can't allow two objects to use parameters with the same name; etc.)
What to do?
I have used the "global collection" alternative in the past.
If you are concerned with naming: how would you handle this in your config file? The way I see it, your global collection is a datastructure representing the same information you have in your config file, so if you have a way of resolving or avoiding name clashes in your cfg-file, you can do the same in your global collection.
I hope you don't feel like I'm thread-jacking you - what you're asking about is similar to what I was thinking about in terms of property aggregation to avoid the models you want to avoid.
I also nicked a bit of the declarative vibe that Elixir has turned me onto.
I'd be curious what the Python gurus of stack overflow think of it and what better alternatives there might be. I don't like big kwargs and if I can avoid big constructors I prefer to.
#!/usr/bin/python
import inspect
from itertools import chain, ifilter
from pprint import pprint
from abc import ABCMeta
class Property(object):
def __init__(self, value=None):
self._x = value
def __repr__(self):
return str(self._x)
def getx(self):
return self._x
def setx(self, value):
self._x = value
def delx(self):
del self._x
value = property(getx, setx, delx, "I'm the property.")
class BaseClass(object):
unique_baseclass_thing = Property()
def get_prop_tree(self):
mro = self.__class__.__mro__
r = []
for i in xrange( 0, len(mro) - 1 ):
child_prop_names = set(dir(mro[i]))
parent_prop_names = set(dir(mro[i+1]))
l_k = list( chain( child_prop_names - parent_prop_names ) )
l_n = [ (x, getattr(mro[i],x,None)) for x in l_k ]
l_p = list( ifilter(lambda y: y[1].__class__ == Property, l_n))
r.append(
(mro[i],
(dict
( l_p )
)
)
)
return r
def get_prop_list(self):
return list( chain(* [ x[1].items() for x in reversed( self.get_prop_tree() ) ] ) )
class SubClass(BaseClass):
unique_subclass_thing = Property(1)
class SubSubClass(SubClass):
unique_subsubclass_thing_one = Property("blah")
unique_subsubclass_thing_two = Property("foo")
if __name__ == '__main__':
a = SubSubClass()
for b in a.get_prop_tree():
print '---------------'
print b[0].__name__
for prop in b[1].keys():
print "\t", prop, "=", b[1][prop].value
print
for prop in a.get_prop_list():
When you run it..
SubSubClass
unique_subsubclass_thing_one = blah
unique_subsubclass_thing_two = foo
---------------
SubClass
unique_subclass_thing = 1
---------------
BaseClass
unique_baseclass_thing = None
unique_baseclass_thing None
unique_subclass_thing 1
unique_subsubclass_thing_one blah
unique_subsubclass_thing_two foo

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