core_analytics\local\indicator\base Class Reference

Abstract base indicator. More...

Inheritance diagram for core_analytics\local\indicator\base:

Public Member Functions
	add_sample_data ($data)
	add_sample_data More...
	calculate ($sampleids, $samplesorigin, $starttime=false, $endtime=false, $existingcalculations=array())
	Calculates the indicator. More...
	clear_sample_data ()
	clear_sample_data More...
	fill_per_analysable_caches (\core_analytics\analysable $analysable)
	Hook to allow indicators to pre-fill data that is shared accross time range calculations. More...
	get_calculation_outcome ($value, $subtype=false)
	Returns how good the calculated value is. More...
	get_display_value ($value, $subtype=false)
	Returns the visible value of the calculated value. More...
	get_id ()
	The class id is the calculable class full qualified class name. More...
	save_calculation_info (\core_analytics\local\time_splitting\base $timesplitting, int $rangeindex)
	Stores in MUC the previously added data and it associates it to the provided $calculable. More...
	should_be_displayed ($value, $subtype)
	Should this value be displayed? More...

Static Public Member Functions
static	get_max_value ()
	Returns the maximum value an indicator calculation can return. More...
static	get_min_value ()
	Returns the minimum value an indicator calculation can return. More...
static	get_name ()
	Returns a lang_string object representing the name for the indicator or target. More...
static	instance ()
	Returns an instance of the indicator. More...
static	required_sample_data ()
	Allows indicators to specify data they need. More...

Public Attributes
const	MAX_VALUE = 1
	Max value an indicator can return.
const	MIN_VALUE = -1
	Min value an indicator can return.
const	OUTCOME_NEGATIVE = 3
	Negative calculation outcome.
const	OUTCOME_NEUTRAL = 0
	Neutral calculation outcome.
const	OUTCOME_OK = 2
	Positive calculation outcome.
const	OUTCOME_VERY_NEGATIVE = 4
	Very negative calculation outcome.
const	OUTCOME_VERY_POSITIVE = 1
	Very positive calculation outcome.

Protected Member Functions
	add_shared_calculation_info (int $sampleid, array $info)
	Adds info related to the current calculation for later use when generating insights. More...
	calculate_sample ($sampleid, $sampleorigin, $starttime, $endtime)
	Calculates the sample. More...
	classify_value ($value, $ranges)
	Classifies the provided value into the provided range according to the ranges predicates. More...
	get_time_range_weeks_number ($starttime, $endtime)
	Returns the number of weeks a time range contains. More...
	limit_value ($calculatedvalue)
	Limits the calculated value to the minimum and maximum values. More...
	retrieve ($elementname, $sampleid)
	Retrieve the specified element associated to $sampleid. More...
	to_features ($calculatedvalues)
	Converts the calculated indicators to dataset feature/s. More...
	validate_calculated_value ($calculatedvalue)
	Validates the calculated value. More...

Protected Attributes
core_analytics calculation_info null	$calculationinfo = null
array[]	$sampledata = array()

Detailed Description

Abstract base indicator.

Copyright

2016 David Monllao

License

http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

Member Function Documentation

add_sample_data()

core_analytics\calculable::add_sample_data (   $data )

inherited

add_sample_data

Parameters

array

$data

Return values

void

add_shared_calculation_info()

core_analytics\calculable::add_shared_calculation_info ( int  $sampleid, array  $info  )

finalprotectedinherited

Adds info related to the current calculation for later use when generating insights.

Note that the data in $info array is reused across multiple samples, if you want to add data just for this sample you can use the sample id as key.

Please, note that you should be careful with how much data you add here as it can kill the server memory.

Parameters

int	$sampleid	The sample id this data is associated with
array	$info	The data. Indexed by an id unique across the site. E.g. an activity id.

Return values

null

calculate()

core_analytics\local\indicator\base::calculate	(		$sampleids,
			$samplesorigin,
			$starttime = false,
			$endtime = false,
			$existingcalculations = array()
	)

Calculates the indicator.

Returns an array of values which size matches $sampleids size.

Parameters

int[]	$sampleids
string	$samplesorigin
integer	$starttime	Limit the calculation to this timestart
integer	$endtime	Limit the calculation to this timeend
array	$existingcalculations	Existing calculations of this indicator, indexed by sampleid.

Return values

array

[0] = [$sampleid => int[]|float[]], [1] = [$sampleid => int|float], [2] = [$sampleid => $sampleid]

calculate_sample()

core_analytics\local\indicator\base::calculate_sample (   $sampleid,   $sampleorigin,   $starttime,   $endtime  )

abstractprotected

Calculates the sample.

Return a value from self::MIN_VALUE to self::MAX_VALUE or null if the indicator can not be calculated for this sample.

Parameters

int	$sampleid
string	$sampleorigin
integer	$starttime	Limit the calculation to this timestart
integer	$endtime	Limit the calculation to this timeend

Return values

float|null

Reimplemented in core_course\analytics\indicator\completion_enabled, core_course\analytics\indicator\no_student, core_course\analytics\indicator\no_teacher, core_course\analytics\indicator\potential_cognitive_depth, core_course\analytics\indicator\potential_social_breadth, core_course\analytics\indicator\activities_due, core\analytics\indicator\any_course_access, core\analytics\indicator\any_write_action, core\analytics\indicator\any_write_action_in_course, core\analytics\indicator\read_actions, core_user\analytics\indicator\user_profile_set, core\analytics\indicator\any_access_after_end, core\analytics\indicator\any_access_before_start, core_user\analytics\indicator\user_track_forums, and core_analytics\local\indicator\community_of_inquiry_activity.

classify_value()

core_analytics\calculable::classify_value (   $value,   $ranges  )

protectedinherited

Classifies the provided value into the provided range according to the ranges predicates.

Use:

• eq as 'equal'
• ne as 'not equal'
• lt as 'lower than'
• le as 'lower or equal than'
• gt as 'greater than'
• ge as 'greater or equal than'

Exceptions

coding_exception

Parameters

int | float	$value
array	$ranges	e.g. [ ['lt', 20], ['ge', 20] ]

Return values

float

clear_sample_data()

core_analytics\calculable::clear_sample_data ( )

inherited

clear_sample_data

Return values

void

fill_per_analysable_caches()

core_analytics\local\indicator\base::fill_per_analysable_caches

(

\core_analytics\analysable

$analysable

)

Hook to allow indicators to pre-fill data that is shared accross time range calculations.

Useful to fill analysable-dependant data that does not depend on the time ranges. Use instance vars to cache data that can be re-used across samples calculations but changes between time ranges (indicator instances are reset between time ranges to avoid unexpected problems).

You are also responsible of emptying previous analysable caches.

Parameters

core_analytics::analysable

$analysable

Return values

void

Reimplemented in core_analytics\local\indicator\community_of_inquiry_activity.

get_calculation_outcome()

core_analytics\calculable::get_calculation_outcome (   $value,   $subtype = false  )

abstractinherited

Returns how good the calculated value is.

Use one of core_analytics::calculable::OUTCOME_* values.

Parameters

float	$value
string | false	$subtype

Return values

int

Reimplemented in core_analytics\local\target\binary, core_analytics\local\target\discrete, core_analytics\local\target\linear, core_analytics\local\indicator\binary, and core_analytics\local\indicator\linear.

get_display_value()

core_analytics\calculable::get_display_value (   $value,   $subtype = false  )

inherited

Returns the visible value of the calculated value.

Parameters

float	$value
string | false	$subtype

Return values

string

Reimplemented in core_analytics\local\target\discrete, core_analytics\local\indicator\binary, core_analytics\local\indicator\discrete, and core_analytics\local\indicator\linear.

get_id()

core_analytics\calculable::get_id ( )

inherited

The class id is the calculable class full qualified class name.

Return values

string

get_max_value()

static core_analytics\local\indicator\base::get_max_value ( )

static

Returns the maximum value an indicator calculation can return.

Return values

float

get_min_value()

static core_analytics\local\indicator\base::get_min_value ( )

static

Returns the minimum value an indicator calculation can return.

Return values

float

get_name()

static core_analytics\calculable::get_name ( )

staticabstractinherited

Returns a lang_string object representing the name for the indicator or target.

Used as column identificator.

If there is a corresponding '_help' string this will be shown as well.

Return values

lang_string

Reimplemented in core_course\analytics\indicator\activities_due, core_course\analytics\indicator\completion_enabled, core_course\analytics\indicator\no_student, core_course\analytics\indicator\no_teacher, core_course\analytics\indicator\potential_cognitive_depth, core_course\analytics\indicator\potential_social_breadth, core_course\analytics\target\course_competencies, core_course\analytics\target\course_completion, core_course\analytics\target\course_dropout, core_course\analytics\target\course_gradetopass, core_course\analytics\target\no_access_since_course_start, core_course\analytics\target\no_recent_accesses, core_course\analytics\target\no_teaching, core\analytics\indicator\any_access_after_end, core\analytics\indicator\any_access_before_start, core\analytics\indicator\any_course_access, core\analytics\indicator\any_write_action, core\analytics\indicator\any_write_action_in_course, core\analytics\indicator\read_actions, mod_assign\analytics\indicator\cognitive_depth, mod_assign\analytics\indicator\social_breadth, mod_book\analytics\indicator\cognitive_depth, mod_book\analytics\indicator\social_breadth, mod_chat\analytics\indicator\cognitive_depth, mod_chat\analytics\indicator\social_breadth, mod_choice\analytics\indicator\cognitive_depth, mod_choice\analytics\indicator\social_breadth, mod_data\analytics\indicator\cognitive_depth, mod_data\analytics\indicator\social_breadth, mod_feedback\analytics\indicator\cognitive_depth, mod_feedback\analytics\indicator\social_breadth, mod_folder\analytics\indicator\cognitive_depth, mod_folder\analytics\indicator\social_breadth, mod_forum\analytics\indicator\cognitive_depth, mod_forum\analytics\indicator\social_breadth, mod_glossary\analytics\indicator\cognitive_depth, mod_glossary\analytics\indicator\social_breadth, mod_imscp\analytics\indicator\cognitive_depth, mod_imscp\analytics\indicator\social_breadth, mod_label\analytics\indicator\cognitive_depth, mod_label\analytics\indicator\social_breadth, mod_lesson\analytics\indicator\cognitive_depth, mod_lesson\analytics\indicator\social_breadth, mod_lti\analytics\indicator\cognitive_depth, mod_lti\analytics\indicator\social_breadth, mod_page\analytics\indicator\cognitive_depth, mod_page\analytics\indicator\social_breadth, mod_quiz\analytics\indicator\cognitive_depth, mod_quiz\analytics\indicator\social_breadth, mod_resource\analytics\indicator\cognitive_depth, mod_resource\analytics\indicator\social_breadth, mod_scorm\analytics\indicator\cognitive_depth, mod_scorm\analytics\indicator\social_breadth, mod_survey\analytics\indicator\cognitive_depth, mod_survey\analytics\indicator\social_breadth, mod_url\analytics\indicator\cognitive_depth, mod_url\analytics\indicator\social_breadth, mod_wiki\analytics\indicator\cognitive_depth, mod_wiki\analytics\indicator\social_breadth, mod_workshop\analytics\indicator\cognitive_depth, mod_workshop\analytics\indicator\social_breadth, core_user\analytics\indicator\user_profile_set, core_user\analytics\indicator\user_track_forums, and core_user\analytics\target\upcoming_activities_due.

get_time_range_weeks_number()

core_analytics\calculable::get_time_range_weeks_number (   $starttime,   $endtime  )

protectedinherited

Returns the number of weeks a time range contains.

Useful for calculations that depend on the time range duration. Note that it returns a float, rounding the float may lead to inaccurate results.

Parameters

int	$starttime
int	$endtime

Return values

float

instance()

static core_analytics\local\indicator\base::instance ( )

static

Returns an instance of the indicator.

Useful to reset cached data.

Return values

core_analytics::local::indicator::base

limit_value()

core_analytics\calculable::limit_value (   $calculatedvalue )

protectedinherited

Limits the calculated value to the minimum and maximum values.

Parameters

float

$calculatedvalue

Return values

float|null

required_sample_data()

static core_analytics\local\indicator\base::required_sample_data ( )

static

Allows indicators to specify data they need.

e.g. A model using courses as samples will not provide users data, but an indicator like "user is hungry" needs user data.

Return values

null|string[]

Name of the required elements (use the database tablename)

Reimplemented in core_analytics\local\indicator\community_of_inquiry_activity, core_course\analytics\indicator\activities_due, core_course\analytics\indicator\completion_enabled, core_course\analytics\indicator\no_student, core_course\analytics\indicator\no_teacher, core_course\analytics\indicator\potential_cognitive_depth, core_course\analytics\indicator\potential_social_breadth, core\analytics\indicator\any_access_after_end, core\analytics\indicator\any_access_before_start, core\analytics\indicator\any_course_access, core\analytics\indicator\any_write_action, core\analytics\indicator\any_write_action_in_course, core\analytics\indicator\read_actions, core_user\analytics\indicator\user_profile_set, and core_user\analytics\indicator\user_track_forums.

retrieve()

core_analytics\calculable::retrieve (   $elementname,   $sampleid  )

protectedinherited

Retrieve the specified element associated to $sampleid.

Parameters

string	$elementname
int	$sampleid

Return values

stdClass|false

An stdClass object or false if it can not be found.

save_calculation_info()

core_analytics\calculable::save_calculation_info ( \core_analytics\local\time_splitting\base  $timesplitting, int  $rangeindex  )

finalinherited

Stores in MUC the previously added data and it associates it to the provided $calculable.

Flagged as final as we don't want people to extend this, it is likely to be moved to core_analytics::calculable

Parameters

core_analytics::local::time_splitting::base	$timesplitting
int	$rangeindex

Return values

null

should_be_displayed()

core_analytics\local\indicator\base::should_be_displayed	(		$value,
			$subtype
	)

Should this value be displayed?

Indicators providing multiple features can be used this method to discard some of them.

Parameters

float	$value
string	$subtype

Return values

bool

Reimplemented in core_analytics\local\indicator\binary, core_analytics\local\indicator\discrete, and core_analytics\local\indicator\linear.

to_features()

core_analytics\local\indicator\base::to_features (   $calculatedvalues )

abstractprotected

Converts the calculated indicators to dataset feature/s.

Parameters

float | int[]

$calculatedvalues

Return values

array

Reimplemented in core_analytics\local\indicator\binary, core_analytics\local\indicator\discrete, and core_analytics\local\indicator\linear.

validate_calculated_value()

core_analytics\local\indicator\base::validate_calculated_value (   $calculatedvalue )

protected

Validates the calculated value.

Exceptions

coding_exception

Parameters

float

$calculatedvalue

Return values

true

Reimplemented in core_analytics\local\indicator\discrete.

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The documentation for this class was generated from the following file:

• analytics/classes/local/indicator/base.php