doc: Add 'Data and user interfaces' page

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Getting started with the management system
==========================================
Using the management system
===========================
In practice, rather than managing experiments by executing :mod:`~artiq.frontend.artiq_run` over and over, most use cases are better served by using the ARTIQ *management system.* This is the high-level part of ARTIQ, which can be used to schedule experiments, distribute and store the results, and manage devices and parameters. It possesses a detailed GUI and can be used on several machines concurrently, allowing them to coordinate with each other and with the specialized hardware over the network. As a result, multiple users on different machines can schedule experiments or retrieve results on the same ARTIQ system, potentially simultaneously.
In practice, rather than managing experiments by executing :mod:`~artiq.frontend.artiq_run` over and over, most use cases are better served by using the ARTIQ *management system*. This is the high-level application part of ARTIQ, which can be used to schedule experiments, manage devices and parameters, and distribute and store results. It also allows for distributed use of ARTIQ, with a single master coordinating demands on the system issued over the network by multiple clients. Using this system, multiple users on different machines can schedule experiments or analyze results on the same ARTIQ system, potentially simultaneously, without interfering with each other.
The management system consists of at least two parts:
a. the **ARTIQ master,** which runs on a single machine, facilitates communication with the core device and peripherals, and is responsible for most of the actual duties of the system,
b. one or more **ARTIQ clients,** which may be local or remote and which communicate only with the master. Both a GUI (the **dashboard**) and a straightforward command line client are provided, with many of the same capabilities.
b. one or more **ARTIQ clients,** which may be local or remote and which communicate only with the master. Both a GUI (the **dashboard**) and a straightforward **command line client** are provided, with many of the same capabilities.
as well as, optionally,
c. one or more **controller managers**, which help coordinate the operation of certain (generally, non-realtime) classes of device.
c. one or more **controller managers**, which coordinate the operation of certain (generally, non-realtime) classes of device and provide certain services to the clients,
d. and one or more instances of the **ARTIQ browser**, a GUI application designed to facilitate the analysis of experiment results and datasets.
In this tutorial, we will explore the basic operation of the management system. Because the various components of the management system run wholly on the host machine, and not on the core device (in other words, they do not inherently involve any kernel functions), it is not necessary to have a core device or any special hardware set up to use it. The examples in this tutorial can all be carried out using only your computer.
In this tutorial, we will explore the basic operation of the management system. Because the various components of the management system run wholly on the host machine, and not on the core device (in other words, they do not inherently involve any kernel functions), it is not necessary to have a core device or any specialized hardware set up to use it. The examples in this tutorial can all be carried out using only your host computer.
Starting your first experiment with the master
----------------------------------------------
Running your first experiment with the master
---------------------------------------------
In the previous tutorial, we used the :mod:`~artiq.frontend.artiq_run` utility to execute our experiments, which is a simple standalone tool that bypasses the management system. We will now see how to run an experiment using the master and the dashboard.
Until now, we have executed experiments using :mod:`~artiq.frontend.artiq_run`, which is a simple standalone tool that bypasses the management system. We will now see how to run an experiment using a master and a client. In this arrangement, the master is responsible for communicating with the core device, scheduling and keeping track of experiments, and carrying out RPCs the core device may call for. Clients submit experiments to the master to be scheduled and, if necessary, query the master about the state of experiments and their results.
First, create a folder ``~/artiq-master`` and copy into it the ``device_db.py`` for your system (your device database, exactly as in :doc:`getting_started_core`.) The master uses the device database in the same way as :mod:`~artiq.frontend.artiq_run` when communicating with the core device. Since no devices are actually used in these examples, you can also use the ``device_db.py`` found in ``examples/no_hardware``.
First, create a folder called ``~/artiq-master``. Copy into it the ``device_db.py`` for your system (your device database, exactly as in :doc:`getting_started_core`); the master uses the device database in the same way as :mod:`~artiq.frontend.artiq_run` when communicating with the core device.
Secondly, create a subfolder ``~/artiq-master/repository`` to contain experiments. By default, the master scans for a folder of this name to determine what experiments are available. If you'd prefer to use a different name, this can be changed by running ``artiq_master -r [folder name]`` instead of ``artiq_master`` below.
.. tip::
Since no devices are actually used in these examples, you can also use a device database in the model of the ``device_db.py`` from ``examples/no_hardware``, which uses resources from ``artiq/sim`` instead of referencing or requiring any real local hardware.
Secondly, create a subfolder ``~/artiq-master/repository`` to contain experiments. By default, the master scans for a folder of this name to determine what experiments are available; if you'd prefer to use a different name, this can be changed by running ``artiq_master -r [folder name]`` instead of ``artiq_master`` below. Experiments don't have to be in the repository to be submitted to the master, but the repository contains those experiments the master is automatically aware of.
Create a very simple experiment in ``~/artiq-master/repository`` and save it as ``mgmt_tutorial.py``: ::
@ -35,141 +39,160 @@ Create a very simple experiment in ``~/artiq-master/repository`` and save it as
def run(self):
print("Hello World")
Start the master with: ::
$ cd ~/artiq-master
$ artiq_master
This last command should not return, as the master keeps running.
This command should display ``ARTIQ master is now ready`` and not return, as the master keeps running. In another terminal, use the client to request this experiment: ::
Now, start the dashboard with the following commands in another terminal: ::
$ artiq_client submit repository/mgmt_tutorial.py
$ cd ~
$ artiq_dashboard
This command should print a message in the format ``RID: 0``, telling you the scheduling ID assigned to the experiment by the master, and exit. Note that it doesn't matter *where* the client is run; the client does not require direct access to ``device_db.py`` or the repository folder, and only directly communicates with the master. Relatedly, the path to an experiment a client submits is given relative to the location of the *master*, not the client.
.. note::
In order to connect to a master over the network, start it with the command ::
Return to the terminal where the master is running. You should see an output similar to: ::
$ artiq_master --bind [hostname or IP]
INFO:worker(0,mgmt_tutorial.py):print:Hello World
In other words, a worker created by the master has executed the experiment, and carried out the print instruction. Congratulations!
.. tip::
In order to run the master and the clients on different PCs, start the master with a ``--bind`` flag: ::
$ artiq_master --bind [hostname or IP to bind to]
and then use the option ``--server`` or ``-s`` for clients, as in: ::
$ artiq_dashboard -s [hostname or IP of the master]
$ artiq_client -s [hostname or IP of the master]
$ artiq_dashboard -s [hostname or IP of the master]
Both IPv4 and IPv6 are supported. See also the individual references at :mod:`~artiq.frontend.artiq_master`, :mod:`~artiq.frontend.artiq_dashboard`, and :mod:`~artiq.frontend.artiq_client`.
Both IPv4 and IPv6 are supported. See also the individual references :mod:`~artiq.frontend.artiq_master`, :mod:`~artiq.frontend.artiq_dashboard`, and :mod:`~artiq.frontend.artiq_client` for more details.
The dashboard should display the list of experiments from the repository folder in a dock called "Explorer". There should be only the experiment we created. Select it and click "Submit", then look at the "Log" dock for the output from this simple experiment.
You may also notice that the master has created some other organizational files in its home directory, notably a folder ``results``, where a HDF5 record is preserved of every experiment that is submitted and run. The files in ``results`` will be discussed in greater detail in :doc:`using_interactivity`.
.. seealso::
You may note that experiments may be submitted with a due date, a priority level, a pipeline identifier, and other specific settings. Some of these are self-explanatory. Many are scheduling-related. For more information on experiment scheduling, especially when submitting longer experiments or submitting across multiple users, see :ref:`experiment-scheduling`.
Running the dashboard and controller manager
--------------------------------------------
.. _mgmt-arguments:
Submitting experiments with :mod:`~artiq.frontend.artiq_client` has some interesting qualities: for instance, experiments can be requested simultaneously by different clients and be relied upon to execute neatly in sequence, which is useful in a distributed context. On the other hand, on an local level, it doesn't necessarily carry many practical advantages over using :mod:`~artiq.frontend.artiq_run`. The real convenience of the management system lies in its GUI, the dashboard. We will now try submitting an experiment using the dashboard.
Adding an argument
------------------
First, start the controller manager: ::
Experiments may have arguments whose values can be set in the dashboard and used in the experiment's code. Modify the experiment as follows: ::
$ artiq_ctlmgr
Like the master, this command should not return, as the controller manager keeps running. Note that the controller manager requires access to the device database, but not in the local directory -- it gets that access automatically by connecting to the master.
.. note::
We will not be using controllers in this part of the tutorial. Nonetheless, the dashboard will expect to be able to contact certain controllers given in the device database, and print error messages if this isn't the case (e.g. ``Is aqctl_moninj_proxy running?``). It is equally possible to check your device database and start the requisite controllers manually, or to temporarily delete their entries from ``device_db.py``, but it's normally quite convenient to let the controller manager handle things. The role and use of controller managers will be covered in more detail in :doc:`using_interactivity`.
In a third terminal, start the dashboard: ::
$ artiq_dashboard
Like :mod:`~artiq.frontend.artiq_client`, the dashboard requires no direct access to the device database or the repository. It communicates with the master to receive information about available experiments and the state of the system.
You should see the list of experiments from the ``repository`` in the dock called 'Explorer'. In our case, this will only be the single experiment we created, listed by the name we gave it in the docstring inside the triple quotes, "Management tutorial". Select it, and in the window that opens, click 'Submit'.
This time you will find the output displayed directly in the dock called 'Log'. The dashboard log combines the master's console output, the dashboard's own logs, and the device logs of the core device itself (if there is one in use); normally, this is the only log it's necessary to check.
Adding a new experiment
-----------------------
Create a new file in your ``repository`` folder, called ``timed_tutorial.py``: ::
from artiq.experiment import *
import time
class TimedTutorial(EnvExperiment):
"""Timed tutorial"""
def build(self):
self.setattr_argument("count", NumberValue(precision=0, step=1))
pass # no devices used
def run(self):
for i in range(self.count):
print("Hello World", i)
:class:`~artiq.language.environment.NumberValue` represents a floating point numeric argument. There are many other types, see :class:`~artiq.language.environment` and :class:`~artiq.language.scan`.
Use the command-line client to trigger a repository rescan: ::
artiq_client scan-repository
The dashboard should now display a spin box that allows you to set the value of the ``count`` argument. Try submitting the experiment as before.
Interactive arguments
---------------------
It is also possible to use interactive arguments, which may be requested and supplied while the experiment is running. This time modify the experiment as follows: ::
def build(self):
pass
def run(self):
repeat = True
while repeat:
print("Hello World")
with self.interactive(title="Repeat?") as interactive:
interactive.setattr_argument("repeat", BooleanValue(True))
repeat = interactive.repeat
time.sleep(10)
print("Goodnight World")
Save it. You will notice that it does not immediately appear in the 'Explorer' dock. For stability reasons, the master operates with a cached idea of the repository, and changes in the file system will often not be reflected until a *repository rescan* is triggered.
Trigger a repository rescan and click the button labeled "Recompute all arguments". Now submit the experiment. It should print once, then wait; in the same dock as "Explorer", find and navigate to the tab "Interactive Args". You can now choose and supply a value for the argument mid-experiment. Every time an argument is requested, the experiment pauses until the input is supplied. If you choose to "Cancel" instead, an :exc:`~artiq.language.environment.CancelledArgsError` will be raised (which the experiment can choose to catch, rather than halting.)
You can ask it to do this through the command-line client: ::
While regular arguments are all requested simultaneously before submitting, interactive arguments can be requested at any point. In order to request multiple interactive arguments at once, place them within the same ``with`` block; see also the example ``interactive.py`` in the ``examples/no_hardware`` folder.
$ artiq_client scan-repository
or you can right-click in the Explorer and select 'Scan repository HEAD'. Now you should be able to select and submit the new experiment.
If you switch the 'Log' dock to its 'Schedule' tab while the experiment is still running, you will see the experiment appear, displaying its RID, status, priority, and other information. Click 'Submit' again while the first experiment is progress, and a second iteration of the experiment will appear in the Schedule, queued up to execute next in line.
.. note::
You may have noted that experiments can be submitted with a due date, a priority level, a pipeline identifier, and other specific settings. Some of these are self-explanatory. Many are scheduling-related. For more information on experiment scheduling, see :ref:`experiment-scheduling`.
In the meantime, you can try out submitting either of the two experiments with different priority levels and take a look at the queues that ensue. If you are interested, you can try submitting experiments through the command line client at the same time, or even open a second dashboard in a different terminal. Observe that no matter the source, all submitted experiments will be accounted for and handled by the scheduler in an orderly way.
.. _master-setting-up-git:
Setting up Git integration
--------------------------
So far, we have used the bare filesystem for the experiment repository, without any version control. Using Git to host the experiment repository helps with the tracking of modifications to experiments and with the traceability of a result to a particular version of an experiment.
So far, we have used the bare filesystem for the experiment repository, without any version control. Using Git to host the experiment repository helps with tracking modifications to experiments and with the traceability to a particular version of an experiment.
.. note::
The workflow we will describe in this tutorial corresponds to a situation where the ARTIQ master machine is also used as a Git server where multiple users may push and pull code. The Git setup can be customized according to your needs; the main point to remember is that when scanning or submitting, the ARTIQ master uses the internal Git data (*not* any working directory that may be present) to fetch the latest *fully completed commit* at the repository's head.
The workflow we will describe in this tutorial corresponds to a situation where the computer running the ARTIQ master is also used as a Git server to which multiple users may contribute code. The Git setup can be customized according to your needs; the main point to remember is that when scanning or submitting, the ARTIQ master uses the internal Git data (*not* any working directory that may be present) to fetch the latest *fully completed commit* at the repository's head. See the :doc:`management_system` page for notes on alternate workflows.
We will use the current ``repository`` folder as working directory for making local modifications to the experiments, move it away from the master data directory, and create a new ``repository`` folder that holds the Git data used by the master. Stop the master with Ctrl-C and enter the following commands: ::
We will use our current ``repository`` folder as the working directory for making local modifications to the experiments, move it away from the master's data directory, and replace it with a new ``repository`` folder, which will hold only the Git data used by the master. Stop the master with Ctrl+C and enter the following commands: ::
$ cd ~/artiq-master
$ mv repository ~/artiq-work
$ mkdir repository
$ cd repository
$ git init --bare
$ git init bare
Now, push data to into the bare repository. Initialize a regular (non-bare) Git repository into our working directory: ::
Now initialize a regular (non-bare) Git repository in our working directory: ::
$ cd ~/artiq-work
$ git init
Then commit our experiment: ::
Then add and commit our experiments: ::
$ git add mgmt_tutorial.py
$ git commit -m "First version of the tutorial experiment"
$ git add timed_tutorial.py
$ git commit -m "First version of the tutorial experiments"
and finally, push the commit into the master's bare repository: ::
and finally, connect the two repositories and push the commit upstream to the master's repository: ::
$ git remote add origin ~/artiq-master/repository
$ git push -u origin master
Start the master again with the ``-g`` flag, telling it to treat the contents of the ``repository`` folder (not ``artiq-work``) as a bare Git repository: ::
.. tip::
If you are not familiar with command-line Git and would like to understand these commands in more detail, search for some tutorials in basic use of Git; there are many available online.
Start the master again with the ``-g`` flag, which tells it to treat its ``repository`` folder as a bare Git repository: ::
$ cd ~/artiq-master
$ artiq_master -g
.. note::
You need at least one commit in the repository before you can start the master.
Note that you need at least one commit in the repository before the master can be started.
There should be no errors displayed, and if you start the GUI again, you will find the experiment there.
Now you should be able to restart the dashboard and see your experiments there.
To complete the master configuration, we must tell Git to make the master rescan the repository when new data is added to it. Create a file ``~/artiq-master/repository/hooks/post-receive`` with the following contents: ::
To make things more convenient, we will make Git tell the master to rescan the repository whenever new data is pushed from downstream. Create a file ``~/artiq-master/repository/hooks/post-receive`` with the following contents: ::
#!/bin/sh
artiq_client scan-repository --async
Then set the execution permission on it: ::
Then set its execution permissions: ::
$ chmod 755 ~/artiq-master/repository/hooks/post-receive
$ chmod 755 repository/hooks/post-receive
.. note::
Remote machines may also push and pull into the master's bare repository using e.g. Git over SSH.
Remote client machines may also push and pull into the master repository, using e.g. Git over SSH.
Let's now make a modification to the experiment. In the source present in the working directory, add an exclamation mark at the end of "Hello World". Before committing it, check that the experiment can still be executed correctly by running it directly from the filesystem using: ::
Let's now make a modification to the experiments. In the working directory ``artiq-work``, open ``mgmt_tutorial.py`` again and add an exclamation mark to the end of "Hello World". Before committing it, check that the experiment can still be executed correctly by submitting it directly from the working directory, using the command-line client: ::
$ artiq_client submit ~/artiq-work/mgmt_tutorial.py
.. note::
You may also use the "Open file outside repository" feature of the GUI, by right-clicking on the explorer.
Alternatively, right-click in the Explorer dock and select the 'Open file outside repository' option for the same effect.
Verify the log in the GUI. If you are happy with the result, commit the new version and push it into the master's repository: ::
@ -177,86 +200,17 @@ Verify the log in the GUI. If you are happy with the result, commit the new vers
$ git commit -a -m "More enthusiasm"
$ git push
.. note::
Notice that commands other than ``git push`` are no longer necessary.
The master should now run the new version from its repository.
As an exercise, add another experiment to the repository, commit and push the result, and verify that it appears in the GUI.
.. _getting-started-datasets:
Datasets
--------
ARTIQ uses the concept of *datasets* to manage the data exchanged with experiments, both supplied *to* experiments (generally, from other experiments) and saved *from* experiments (i.e. results or records).
Modify the experiment as follows, once again using a single non-interactive argument: ::
def build(self):
self.setattr_argument("count", NumberValue(precision=0, step=1))
def run(self):
self.set_dataset("parabola", np.full(self.count, np.nan), broadcast=True)
for i in range(self.count):
self.mutate_dataset("parabola", i, i*i)
time.sleep(0.5)
.. tip::
You need to import the ``time`` module, and the ``numpy`` module as ``np``.
Commit, push and submit the experiment as before. Go to the "Datasets" dock of the GUI and observe that a new dataset has been created. Once the experiment has finished executing, navigate to ``~/artiq-master/`` in a terminal or file manager and see that a new directory has been created called ``results``. Your dataset should be stored as an HD5 dump file in ``results`` under ``<date>/<hour>``.
.. note::
By default, datasets are primarily attributes of the experiments that run them, and are not shared with the master or the dashboard. The ``broadcast=True`` argument specifies that an argument should be shared in real-time with the master, which is responsible for dispatching it to the clients. A more detailed description of dataset methods and their arguments can be found under :mod:`artiq.language.environment.HasEnvironment`.
Open the file for your first dataset with HDFView, h5dump, or any similar third-party tool, and observe the data we just generated as well as the Git commit ID of the experiment (a hexadecimal hash such as ``947acb1f90ae1b8862efb489a9cc29f7d4e0c645`` which represents a particular state of the Git repository). A list of Git commit IDs can be found by running the ``git log`` command in ``~/artiq-master/``.
Applets
-------
Often, rather than the HDF dump, we would like to see our result datasets in readable graphical form, preferably immediately. In the ARTIQ dashboard, this is achieved by programs called "applets". Applets are independent programs that add simple GUI features and are run as separate processes (to achieve goals of modularity and resilience against poorly written applets). ARTIQ supplies several applets for basic plotting in the :mod:`artiq.applets` module, and users may write their own using the provided interfaces.
.. seealso::
For developing your own applets, see the references provided on the :ref:`management system page<applet-references>` of this manual.
For our ``parabola`` dataset, we will create an XY plot using the provided :mod:`artiq.applets.plot_xy`. Applets are configured with simple command line options; we can find the list of available options using the ``-h`` flag. Try running: ::
$ python3 -m artiq.applets.plot_xy -h
In our case, we only need to supply our dataset as the y-values to be plotted. Navigate to the "Applet" dock in the dashboard. Right-click in the empty list and select "New applet from template" and "XY". This will generate a version of the applet command that shows all applicable options; edit the command so that it retrieves the ``parabola`` dataset and erase the unused options. The line should now be: ::
${artiq_applet}plot_xy parabola
Run the experiment again, and observe how the points are added one by one to the plot.
RTIO analyzer and the dashboard
-------------------------------
The :ref:`rtio-analyzer-example` is fully integrated into the dashboard. Navigate to the "Waveform" tab in the dashboard. After running the example experiment in that section, or any other experiment producing an analyzer trace, the waveform results will be directly displayed in this tab. It is also possible to save a trace, reopen it, or export it to VCD directly from the GUI.
Non-RTIO devices and the controller manager
-------------------------------------------
As described in :doc:`rtio`, there are two classes of equipment a laboratory typically finds itself needing to operate. So far, we have largely discussed ARTIQ in terms of one only: the kind of specialized hardware that requires the very high-resolution timing control ARTIQ provides. The other class comprises the broad range of regular, "slow" laboratory devices, which do *not* require nanosecond precision and can generally be operated perfectly well from a regular PC over a non-realtime channel such as USB.
To handle these "slow" devices, ARTIQ uses *controllers*, intermediate pieces of software which are responsible for the direct I/O to these devices and offer RPC interfaces to the network. Controllers can be started and run standalone, but are generally handled through the *controller manager*, available through the ``artiq-comtools`` package (normally automatically installed together with ARTIQ.) The controller manager in turn communicates with the ARTIQ master, and through it with clients or the GUI.
To start the controller manager (the master must already be running), the only command necessary is: ::
$ artiq_ctlmgr
Controllers may be run on a different machine from the master, or even on multiple different machines, alleviating cabling issues and OS compatibility problems. In this case, communication with the master happens over the network. If multiple machines are running controllers, they must each run their own controller manager (for which only ``artiq-comtools`` and its few dependencies are necessary, not the full ARTIQ installation.) Use the ``-s`` and ``--bind`` flags of :mod:`~artiq_comtools.artiq_ctlmgr` to set IP addresses or hostnames to connect and bind to.
Note, however, that the controller for the particular device you are trying to connect to must first exist and be part of a complete Network Device Support Package, or NDSP. :doc:`Some NDSPs are already available <list_of_ndsps>`. If your device is not on this list, the system is designed to make it quite possible to write your own. For this, see the :doc:`developing_a_ndsp` page.
Once a device is correctly listed in ``device_db.py``, it can be added to an experiment using ``self.setattr_device([device_name])`` and the methods its API offers called straightforwardly as ``self.[device_name].[method_name]``. As long as the requisite controllers are running and available, the experiment can then be executed with :mod:`~artiq.frontend.artiq_run` or through the management system.
Notice that commands other than ``git commit`` and ``git push`` are no longer necessary. The Git hook should cause a repository rescan automatically, and submitting the experiment in the dashboard should run the new version, with enthusiasm included.
The ARTIQ session
-----------------
If (as is often the case) you intend to mostly operate your ARTIQ system and its devices from a single machine, i.e., the networked aspects of the management system are largely unnecessary and you will be running master, dashboard, and controller manager on one computer, they can all be started simultaneously with the single command: ::
Often, you will want to run an instance of the controller manager and dashboard along with the ARTIQ master, whether or not you also intend to allow other clients to connect remotely. For convenience, all three can be started simultaneously with a single command: ::
$ artiq_session
Arguments to the individuals (including ``-s`` and ``--bind``) can still be specified using the ``-m``, ``-d`` and ``-c`` options respectively. See also :mod:`~artiq.frontend.artiq_session`.
Arguments to the individual tools (including ``-s`` and ``--bind``) can still be specified using the ``-m``, ``-d`` and ``-c`` options for master, dashboard and manager respectively. Use an equals sign to avoid confusion in parsing, for example: ::
$ artiq_session -m=-g
to start the session with the master in Git mode. See also :mod:`~artiq.frontend.artiq_session`.

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rtio
getting_started_core
getting_started_mgmt
using_data_interfaces
using_drtio_subkernels
.. toctree::

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Data and user interfaces
========================
Beyond running single experiments, or basic use of master, client, and dashboard, ARTIQ supports a much broader range of interactions between its different components. These integrations allow for system control which is extensive, flexible, and dynamic, with space for different workflows and methodologies depending on the needs of particular sets of experiments. We will now explore some of these further tools and systems.
.. note::
This page follows up directly on :doc:`getting_started_mgmt`, but discusses a broader range of features, most of which continue to rest on the foundation of the management system. Some sections (datasets, the browser) are still possible to try out using your PC alone; others (MonInj, the RTIO analyzer) are only meaningful in relation to some kind of real-time hardware.
.. _mgmt-datasets:
Datasets and results
--------------------
ARTIQ uses the concept of *datasets* to manage the data exchanged with experiments, both supplied *to* experiments (generally, from other experiments) and saved *from* experiments (i.e. results or records). We will now see how to view and manipulate datasets, both in experiments or through the management system. Create a new experiment as follows: ::
from artiq.experiment import *
import numpy as np
import time
class Datasets(EnvExperiment):
"""Dataset tutorial"""
def build(self):
pass # no devices used
def run(self):
self.set_dataset("parabola", np.full(10, np.nan), broadcast=True)
for i in range(10):
self.mutate_dataset("parabola", i, i*i)
time.sleep(0.5)
Save it as ``dataset_tutorial.py``. Commit and push your changes, or rescan the repository, whichever is appropriate for your management system configuration. Submit the experiment. In the same window as 'Explorer', navigate to the 'Dataset' tab and observe that a new dataset has been created under the name ``parabola``. As the experiment runs, the values are progressively calculated and entered.
.. note::
By default, datasets are primarily attributes of the experiments that run them, and are not shared with the master or the dashboard. The ``broadcast=True`` argument specifies that a dataset should be shared in real-time with the master, which is then responsible for storing it in the dataset database ``dataset_db.mdb`` and dispatching it to any clients. For more about dataset options see the :ref:`Environment <environment-datasets>` page.
As long as ``archive=False`` is not explicitly set, datasets are among the information preserved by the master in the ``results`` folder. The files in ``results`` are organized in subdirectories based on the time they were executed, as ``results/<date>/<hour>/``; their individual filenames are a combination of the RID assigned to the execution and the name of the experiment module itself. As such, results are stored in a unique and identifiable location for each iteration of an experiment, even if a dataset is overwritten in the master.
You can open the result file for this experiment with HDFView, h5dump, or any similar third-party tool. Observe that it contains the dataset we just generated, as well as other useful information such as RID, run time, start time, and the Git commit ID of the repository at the time of the experiment (a hexadecimal hash such as ``947acb1f90ae1b8862efb489a9cc29f7d4e0c645``).
.. tip::
If you are not familiar with Git, try running ``git log`` in either of your connected Git repositories to see a history of commits in the repository which includes their respective hashes. As long as this history remains intact, you can use a hash of this kind of to uniquely identify, and even retrieve, the state of the files in the repository at the time this experiment was run. In oher words, when running experiments from a Git repository, it's always possible to retrieve the code that led to a particular set of results.
Applets
^^^^^^^
Most of the time, rather than the HDF dump, we would like to see our result datasets in a readable graphical form, preferably without opening any third-party applications. In the ARTIQ dashboard, this is achieved by programs called "applets". Applets provide simple, modular GUI features; are run independently from the dashboard as separate processes to achieve goals of modularity and resilience. ARTIQ supplies several applets for basic plotting in the :mod:`artiq.applets` module, and provides interfaces so users can write their owns.
.. seealso::
For more about developing your own applets, see the references provided on the :ref:`Management system reference<applet-references>` page of this manual.
For our ``parabola`` dataset, we will create an XY plot using the provided :mod:`artiq.applets.plot_xy`. Applets are configured with simple command line options. To figure out what configurations are accepted, use the ``-h`` flag, as in: ::
$ python3 -m artiq.applets.plot_xy -h
In our case, we only need to supply our dataset to the applet to be plotted. Navigate to the "Applet" dock in the dashboard. Right-click in the empty list and select "New applet from template" and "XY". This will generate a version of the applet command which shows all the configuration options; edit the line so that it retrieves the ``parabola`` dataset and erase the unused options. It should look like: ::
${artiq_applet}plot_xy parabola
Run the experiment again, and observe how the points are added as they are generated to the plot in the applet window.
The ARTIQ browser
^^^^^^^^^^^^^^^^^
ARTIQ also possesses a second GUI, specifically targeted for the manipulation and analysis of datasets, called the ARTIQ browser. It is independent, and does not require either a running master or a core device to operate; a connection to the master is only necessary if you want to upload edited datasets back to the main management system. Open ``results`` in the browser by running: ::
$ cd ~/artiq-master
$ artiq_browser ./results
Navigate to the entry containing your ``parabola`` datasets in the file explorers on the left. To bring the dataset into the browser, click on the HDF5 file.
To open an experiment, click on 'Experiment' at the top left. Observe that instead of 'Submit', the option given is 'Analyze'. Where :mod:`~artiq.frontend.artiq_run` and :mod:`~artiq.frontend.artiq_master` ultimately call :meth:`~artiq.language.environment.Experiment.prepare`, :meth:`~artiq.language.environment.Experiment.run`, and :meth:`~artiq.language.environment.Experiment.analyze`, the browser limits itself to :meth:`~artiq.language.environment.Experiment.analyze`. Nonetheless, it still accepts arguments.
As described later in :ref:`experiment-scheduling`, only :meth:`~artiq.language.environment.Experiment.run` is obligatory for experiments to implement, and only :meth:`~artiq.language.environment.Experiment.run` is permitted to access hardware; the preparation and analysis stages occur before and after, and are limited to the host machine. The browser allows for re-running the post-experiment :meth:`~artiq.language.environment.Experiment.analyze`, potentially with different arguments or an edited algorithm, while accessing the datasets from opened ``results`` files.
Notably, the browser does not merely act as an HD5 viewer, but also allows the use of ARTIQ applets to plot and view the data. For this, see the lower left dock; applets can be opened, closed, and managed just as they are in the dashboard, once again accessing datasets from ``results``.
.. _mgmt-ctlmgr:
Non-RTIO devices and the controller manager
-------------------------------------------
As described in :doc:`rtio`, there are two classes of equipment a laboratory typically finds itself needing to operate. So far, we have largely discussed ARTIQ in terms of one only: the kind of specialized hardware that requires the very high-resolution timing control ARTIQ provides. The other class comprises the broad range of regular, "slow" laboratory devices, which do *not* require nanosecond precision and can generally be operated perfectly well from a regular PC over a non-realtime channel such as USB.
To handle these "slow" devices, ARTIQ uses *controllers*, intermediate pieces of software which are responsible for the direct I/O to these devices and offer RPC interfaces to the network. By convention, ARTIQ controllers are named with the prefix ``aqctl_``. Controllers can be started and run standalone, but are generally handled through the *controller manager*, :mod:`~artiq_comtools.artiq_ctlmgr`. The controller manager in turn communicates with the ARTIQ master, and through it with clients or the GUI.
Like clients, controllers do not need to be run on the same machine as the master. Various controllers in a device database may in fact be distributed across multiple machines, in whatever way is most convenient for the devices in question, alleviating cabling issues and OS compatibility problems. Each machine running controllers must run its own controller manager. Communication with the master happens over the network. Use the ``-s`` flag of :mod:`~artiq_comtools.artiq_ctlmgr` to set the IP address or hostname of a master to bind to.
.. tip::
The controller manager is made available through the ``artiq-comtools`` package, maintained separately from the main ARTIQ repository. It is considered a dependency of ARTIQ, and is normally included in any ARTIQ installation, but can also be installed independently. This is especially useful when controllers are widely distributed; instead of installing ARTIQ on every machine that runs controllers, only ``artiq-comtools`` and its much lighter set of dependencies are necessary. See the source repository `here <https://github.com/m-labs/artiq-comtools>`_.
We have already used the controller manager in the previous part of the tutorial. To run it, the only command necessary is: ::
$ artiq_ctlmgr
Note however that in order for the controller manager to be able to start a controller, the controller in question must first exist and be properly installed on the machine the manager is running on. For laboratory devices, this normally means it must be part of a complete Network Device Support Package, or NDSP. :doc:`Some NDSPs are already available <list_of_ndsps>`. If your device is not on this list, the protocol is designed to make it relatively simple to write your own; for more information and a tutorial, see the :doc:`developing_a_ndsp` page.
Once a device is correctly listed in ``device_db.py``, it can be added to an experiment using ``self.setattr_device([device_name])`` and the methods its API offers called straightforwardly as ``self.[device_name].[method_name]``. As long as the requisite controllers are running and available, the experiment can then be executed with :mod:`~artiq.frontend.artiq_run` or through the management system. To understand how to add controllers to the device database, see also :ref:`device-db`.
ARTIQ built-in controllers
^^^^^^^^^^^^^^^^^^^^^^^^^^
Certain built-in controllers are also included in a standard ARTIQ installation, and can be run directly in your ARTIQ shell. They are listed at the end of the :ref:`Utilities <utilities-ctrls>` reference (the commands prefixed with ``aqctl_`` rather than ``artiq_``) and included by default in device databases generated with :mod:`~artiq.frontend.artiq_ddb_template`.
Broadly speaking, these controllers are edge cases, serving as proxies for interactions between clients and the core device, which otherwise do not make direct contact with each other. Features like dashboard MonInj and the RTIO analyzer's Waveform tab, both discussed in more depth below, depend upon a respective proxy controller to function. A proxy controller is also used to communicate the core log to dashboards.
Although they are listed in the references for completeness' sake, there is normally no reason to run the built-in controllers independently. A controller manager run alongside the master (or anywhere else, provided the given addresses are edited accordingly; proxy controllers communicate with the core device by network just as the master does) is more than sufficient.
Using MonInj
------------
One of ARTIQ's most convenient features is the Monitor/Injector, commonly known as MonInj. This feature allows for checking (monitoring) the state of various peripherals and setting (injecting) values for their parameters, directly and without any need to explicitly run an experiment for either. MonInj is integrated into ARTIQ on a gateware level, and (except in the case of injection on certain peripherals) can be used in parallel to running experiments, without interrupting them.
In order to use dashboard MonInj, ``aqctl_moninj_proxy`` or a local controller manager must be running. Given this, navigate to the dashboard's ``MonInj`` tab. Mouse over the second button at the top of the dock, which is labeled 'Add channels'. Clicking on it will open a small pop-up, which allows you to select RTIO channels from those currently available in your system.
.. note::
Multiple channels can be selected and added simultaneously. The button with a folder icon allows opening independent pop-up MonInj docks, into which channels can also be added. Configurations of docks and channels will be remembered between dashboard restarts.
.. warning::
Not all ARTIQ/Sinara real-time peripherals support both monitoring *and* injection, and some do not yet support either. Which peripherals belong to which categories has varied somewhat over the history of ARTIQ versions. Depending on the complexity of the peripheral, incorporating monitor or injection support represents a nontrivial engineering effort, which has generally only been undertaken when commissioned by particular research groups or users. The pop-up menu will display only channels that are valid targets for one or the other functionality.
For DDS/Urukul in particular, injection is supported by a slightly different implementation, which involves automatic submission of a miniature kernel which will override and terminate any other experiments currently executing. Accordingly, Urukul injection should be used carefully.
MonInj can always be tested using the user LEDs, which you can find the folder ``ttl`` in the pop-up menu. Channels are listed according to the types and names given in ``device_db.py``. Add your LED channels to the main dock; their monitored values will be displayed automatically. Try running any experiment that has an effect on LED state to see the monitored values change.
Mouse over one of the LED channel fields to see the two buttons ``OVR``, for override, and ``LVL``, for level. Clicking 'Override' will cause MonInj to take direct control of the channel, overriding any experiments that may be running. Once the channel is overriden, its level can be changed directly from the dashboard, by clicking 'Level' to flip it back and forth.
Command-line monitor
^^^^^^^^^^^^^^^^^^^^
For those peripherals which support monitoring, the command-line :mod:`~artiq.frontend.artiq_rtiomon` utility can be used to see monitor output directly in the terminal. The command-line monitor does not require or interact with the management system or even the device database. Instead, it takes the core device IP address and a channel number as parameters and communicates with the core device directly.
This tool is very simple, and there is rarely any reason to prefer its use over the dashboard monitor. Nonetheless, it can be helpful for certain kinds of debugging.
.. RTIO analyzer and Waveform
.. --------------------------
.. TBI.
Shortcuts
---------
The last notable tab of the dashboard is called 'Shortcuts'. To demonstrate its use, navigate to the 'Explorer' tab, left-click on an experiment, and select 'Set shortcut'. Binding an experiment to one of the available keys will cause it to be automatically submitted any time the key is pressed. The 'Shortcuts' tab simply displays the current set of bound experiments, and provides controls for opening a submission window or deleting the shortcut.
.. note::
Experiments submitted by shortcut will always use the argument currently entered into the submission window, if one is open. If no window is currently open, it will simply use the value *last* entered into a submission window. This is true even if that value was never used to submit an experiment.