Debug Output

DebugAction

A DebugAction is a small functor to print/issue debug output. The usual call is given by (amp::AbstractManoptProblem, ams::AbstractManoptSolverState, i) -> s, where i is the current iterate.

By convention i=0 is interpreted as "For Initialization only", i.e. only debug info that prints initialization reacts, i<0 triggers updates of variables internally but does not trigger any output. Finally typemin(Int) is used to indicate a call from stop_solver! that returns true afterwards.

Fields (assumed by subtypes to exist)

• print method to perform the actual print. Can for example be set to a file export,

or to @info. The default is the print function on the default Base.stdout.

DebugChange(M=DefaultManifold())

debug for the amount of change of the iterate (stored in get_iterate(o) of the AbstractManoptSolverState) during the last iteration. See DebugEntryChange for the general case

Keyword Parameters

• storage – (StoreStateAction( [:Gradient] )) – (eventually shared) the storage of the previous action
• prefix – ("Last Change:") prefix of the debug output (ignored if you set format)
• io – (stdout) default steream to print the debug to.
• format - ( "$prefix %f") format to print the output using an sprintf format.
• inverse_retraction_method - (default_inverse_retraction_method(M)) the inverse retraction to be used for approximating distance.

DebugCost <: DebugAction

print the current cost function value, see get_cost.

Constructors

DebugCost()

Parameters

• format - ("$prefix %f") format to print the output using sprintf and a prefix (see long).
• io – (stdout) default steream to print the debug to.
• long - (false) short form to set the format to f(x): (default) or current cost: and the cost

DebugDivider <: DebugAction

print a small divider (default " | ").

Constructor

DebugDivider(div,print)

DebugEntry <: DebugAction

print a certain fields entry of type {T} during the iterates, where a format can be specified how to print the entry.

Addidtional Fields

• field – Symbol the entry can be accessed with within AbstractManoptSolverState

Constructor

DebugEntry(f; prefix="$f:", format = "$prefix %s", io=stdout)

DebugEntryChange{T} <: DebugAction

print a certain entries change during iterates

Additional Fields

• print – (print) function to print the result
• prefix – ("Change of :Iterate") prefix to the print out
• format – ("$prefix %e") format to print (uses the `prefix by default and scientific notation)
• field – Symbol the field can be accessed with within AbstractManoptSolverState
• distance – function (p,o,x1,x2) to compute the change/distance between two values of the entry
• storage – a StoreStateAction to store the previous value of :f

Constructors

DebugEntryChange(f,d)

Keyword arguments

• io (stdout) an IOStream
• prefix ("Change of $f")
• storage (StoreStateAction((f,))) a StoreStateAction
• initial_value an initial value for the change of o.field.
• format – ("$prefix %e") format to print the change

DebugEvery <: DebugAction

evaluate and print debug only every $i$th iteration. Otherwise no print is performed. Whether internal variables are updates is determined by always_update.

This method does not perform any print itself but relies on it's childrens print.

Constructor

DebugEvery(d::DebugAction, every=1, always_update=true)

Initialise the DebugEvery.

DebugGradientChange()

debug for the amount of change of the gradient (stored in get_gradient(o) of the AbstractManoptSolverState o) during the last iteration. See DebugEntryChange for the general case

Keyword Parameters

• storage – (StoreStateAction( (:Gradient,) )) – (eventually shared) the storage of the previous action
• prefix – ("Last Change:") prefix of the debug output (ignored if you set format)
• io – (stdout) default steream to print the debug to.
• format - ( "$prefix %f") format to print the output using an sprintf format.

DebugGroup <: DebugAction

group a set of DebugActions into one action, where the internal prints are removed by default and the resulting strings are concatenated

Constructor

DebugGroup(g)

construct a group consisting of an Array of DebugActions g, that are evaluated en bloque; the method does not perform any print itself, but relies on the internal prints. It still concatenates the result and returns the complete string

DebugIfEntry <: DebugAction

Issue a warning, info or error if a certain field does not pass a check

Fields

• io – an io stream
• check – a function that takes the value of the field as input and returns a boolean
• field – Symbol the entry can be accessed with within AbstractManoptSolverState
• msg - is the check fails, this message is displayed
• type – Symbol specifying the type of display, possible values :print, : warn, :info, :error, where :print prints to io.

Constructor

DebugEntry(field, check=(>(0)); type=:warn, message=":$f is nonnegative", io=stdout)

DebugIterate <: DebugAction

debug for the current iterate (stored in get_iterate(o)).

Constructor

DebugIterate()

Parameters

• io – (stdout) default steream to print the debug to.
• long::Bool whether to print x: or current iterate

DebugIteration <: DebugAction

Constructor

DebugIteration()

Keyword parameters

• format - ("# %-6d") format to print the output using an sprintf format.
• io – (stdout) default steream to print the debug to.

debug for the current iteration (prefixed with # by )

DebugMessages <: DebugAction

An AbstractManoptSolverState or one of its substeps like a Stepsize might generate warnings throughout their compuations. This debug can be used to :print them display them as :info or :warnings or even :error, depending on the message type.

Constructor

DebugMessages(mode=:Info; io::IO=stdout)

Initialize the messages debug to a certain mode. Available modes are

• :Error – issue the messages as an error and hence stop at any issue occuring
• :Info – issue the messages as an @info
• :Print – print messages to the steam io.
• :Warning – issue the messages as a warning

DebugSolverState <: AbstractManoptSolverState

The debug options append to any options a debug functionality, i.e. they act as a decorator pattern. Internally a Dictionary is kept that stores a DebugAction for several occasions using a Symbol as reference. The default occasion is :All and for example solvers join this field with :Start, :Step and :Stop at the beginning, every iteration or the end of the algorithm, respectively

The original options can still be accessed using the get_state function.

Fields (defaults in brackets)

• options – the options that are extended by debug information
• debugDictionary – a Dict{Symbol,DebugAction} to keep track of Debug for different actions

Constructors

DebugSolverState(o,dA)

construct debug decorated options, where dD can be

• a DebugAction, then it is stored within the dictionary at :All
• an Array of DebugActions, then it is stored as a debugDictionary within :All.
• a Dict{Symbol,DebugAction}.
• an Array of Symbols, String and an Int for the DebugFactory

DebugStoppingCriterion <: DebugAction

print the Reason provided by the stopping criterion. Usually this should be empty, unless the algorithm stops.

DebugTime()

Measure time and print the intervals. Using start=true you can start the timer on construction, for example to measure the runtime of an algorithm overall (adding)

The measured time is rounded using the given time_accuracy and printed after canonicalization.

Keyword Parameters

• prefix – ("Last Change:") prefix of the debug output (ignored if you set format)
• io – (stdout) default steream to print the debug to.
• format - ( "$prefix %s") format to print the output using an sprintf format, where %s is the canonicalized time`.
• mode – (:cumulative) whether to display the total time or reset on every call using :iterative.
• start – (false) indicate whether to start the timer on creation or not. Otherwise it might only be started on firsr call.
• time_accuracy – (Millisecond(1)) round the time to this period before printing the canonicalized time

DebugWarnIfCostIncreases <: DebugAction

print a warning if the cost increases.

Note that this provides an additional warning for gradient descent with its default constant step size.

Constructor

DebugWarnIfCostIncreases(warn=:Once; tol=1e-13)

Initialize the warning to warning level (:Once) and introduce a tolerance for the test of 1e-13.

The warn level can be set to :Once to only warn the first time the cost increases, to :Always to report an increase every time it happens, and it can be set to :No to deactivate the warning, then this DebugAction is inactive. All other symbols are handled as if they were :Always:

DebugWarnIfCostNotFinite <: DebugAction

A debug to see when a field (value or array within the AbstractManoptSolverState is or contains values that are not finite, for example Inf or Nan.

Constructor

DebugWarnIfCostNotFinite(field::Symbol, warn=:Once)

Initialize the warning to warn :Once.

This can be set to :Once to only warn the first time the cost is Nan. It can also be set to :No to deactivate the warning, but this makes this Action also useless. All other symbols are handled as if they were :Always:

DebugWarnIfFieldNotFinite <: DebugAction

A debug to see when a field from the options is not finite, for example Inf or Nan

Constructor

DebugWarnIfFieldNotFinite(field::Symbol, warn=:Once)

Initialize the warning to warn :Once.

This can be set to :Once to only warn the first time the cost is Nan. It can also be set to :No to deactivate the warning, but this makes this Action also useless. All other symbols are handled as if they were :Always:

Example

DebugWaranIfFieldNotFinite(:Gradient)

Creates a [DebugAction] to track whether the gradient does not get Nan or Inf.

DebugWhenActive <: DebugAction

evaluate and print debug only if the active boolean is set. This can be set from outside and is for example triggered by DebugEvery on debugs on the subsolver.

This method does not perform any print itself but relies on it's childrens print.

For now, the main interaction is with DebugEvery which might activate or deactivate this debug

Fields

• always_update – whether or not to call the order debugs with iteration -1 in in active state
• active – a boolean that can (de-)activated from outside to enable/disable debug

Constructor

DebugWhenActive(d::DebugAction, active=true, always_update=true)

Initialise the DebugSubsolver.

DebugActionFactory(s)

create a DebugAction where

• a Stringyields the correspoinding divider
• a DebugAction is passed through
• a [Symbol] creates DebugEntry of that symbol, with the exceptions of :Change, :Iterate, :Iteration, and :Cost.
• a Tuple{Symbol,String} creates a DebugEntry of that symbol where the String specifies the format.

DebugActionFactory(s::Symbol)

Convert certain Symbols in the debug=[ ... ] vector to DebugActions Currently the following ones are done. Note that the Shortcut symbols should all start with a capital letter.

• :Cost creates a DebugCost
• :Change creates a DebugChange
• :GradientChange creates a DebugGradientChange
• :GradientNorm creates a DebugGradientNorm
• :Iterate creates a DebugIterate
• :Iteration creates a DebugIteration
• :IterativeTime creates a DebugTime(:Iterative)
• :Stepsize creates a DebugStepsize
• :WarnCost creates a DebugWarnIfCostNotFinite
• :WarnGradient creates a DebugWarnIfFieldNotFinite for the ::Gradient.
• :Time creates a DebugTime
• :WarningMessagescreates a DebugMessages(:Warning)
• :InfoMessagescreates a DebugMessages(:Info)
• :ErrorMessages creates a DebugMessages(:Error)
• :Messages creates a DebugMessages() (i.e. the same as :InfoMessages)

any other symbol creates a DebugEntry(s) to print the entry (o.:s) from the options.

DebugActionFactory(t::Tuple{Symbol,String)

Convert certain Symbols in the debug=[ ... ] vector to DebugActions Currently the following ones are done, where the string in t[2] is passed as the format the corresponding debug. Note that the Shortcut symbols t[1] should all start with a capital letter.

• :Cost creates a DebugCost
• :Change creates a DebugChange
• :GradientChange creates a DebugGradientChange
• :Iterate creates a DebugIterate
• :Iteration creates a DebugIteration
• :Stepsize creates a DebugStepsize
• :Time creates a DebugTime
• :IterativeTime creates a DebugTime(:Iterative)

any other symbol creates a DebugEntry(s) to print the entry (o.:s) from the options.

DebugFactory(a)

given an array of Symbols, Strings DebugActions and Ints

• The symbol :Stop creates an entry of to display the stopping criterion at the end (:Stop => DebugStoppingCriterion()), for further symbols see DebugActionFactory
• The symbol :Subsolver wraps all dictionary entries with DebugWhenActive that can be set from outside.
• Tuples of a symbol and a string can be used to also specify a format, see DebugActionFactory
• any string creates a DebugDivider
• any DebugAction is directly included
• an Integer kintroduces that debug is only printed every kth iteration

Return value

This function returns a dictionary with an entry :All containing one general DebugAction, possibly a DebugGroup of entries. It might contain an entry :Start, :Step, :Stop with an action (each) to specify what to do at the start, after a step or at the end of an Algorithm, respectively. On all three occastions the :All action is exectued. Note that only the :Stop entry is actually filled when specifying the :Stop symbol.

Example

The array

[:Iterate, " | ", :Cost, :Stop, 10]

Adds a group to :All of three actions (DebugIteration, DebugDivider with " | " to display, DebugCost) as a DebugGroup inside an DebugEvery to only be executed every 10th iteration. It also adds the DebugStoppingCriterion to the :Stop entry of the dictionary.

reset!(d::DebugTime)

reset the internal time of a DebugTime, that is start from now again.

stop!(d::DebugTime)

stop the reset the internal time of a DebugTime, that is set the time to 0 (undefined)

initialize_solver!(amp::AbstractManoptProblem, dss::DebugSolverState)

Extend the initialization of the solver by a hook to run debug that were added to the :Start and :All entries of the debug lists.

step_solver!(amp::AbstractManoptProblem, dss::DebugSolverState, i)

Extend the ith step of the solver by a hook to run debug prints, that were added to the :Step and :All entries of the debug lists.

stop_solver!(amp::AbstractManoptProblem, dss::DebugSolverState, i)

Extend the check, whether to stop the solver by a hook to run debug, that were added to the :Stop and :All entries of the debug lists.