`<matchesPattern>`

Boolean condition that tests whether input matches a math pattern

<matchesPattern> is an Evaluation component that returns the boolean value of true or false depending on whether the enclosed math (often a referenced <mathInput/>) conforms to the specified pattern template.

Attributes and Properties

Attributes for `<matchesPattern>`

Other (19)

allowedErrorInNumbers

number. Default value: 0. Maximum allowed numeric error when comparing numbers.

allowedErrorIsAbsolute

boolean. Default value: false. Whether allowedErrorInNumbers is interpreted as an absolute (rather than relative) tolerance.

allowImplicitIdentities

boolean. Default value: false. Whether to allow implicit identity transformations when matching.

allowPermutations

boolean. Default value: true. Whether to allow permutations of operands when matching.

caseInsensitiveMatch

boolean. Default value: false. Whether text comparisons ignore letter case.

excludeMatches

mathList. Patterns whose matches are excluded.

expandOnCompare

boolean. Default value: false. Whether to expand math expressions before comparing.

includeErrorInNumberExponents

boolean. Default value: false. Whether the allowed numeric error also applies to numbers in exponents.

matchBlanks

boolean. Default value: false. Whether unfilled blanks in a math expression count as a match.

matchByExactPositions

boolean. Default value: false. Whether to match list values by exact position rather than by content.

matchExpressionWithBlanks

boolean. Default value: false. Whether to allow expressions with blanks to match.

numPeriodicSetMatchesRequired

integer. Default value: 3. Number of consecutive elements of a periodic set required to count as a match.

numSignErrorsMatched

number. Default value: 0. Maximum number of sign errors that still count as a match.

pattern

math. Math expression pattern to match against.

requireNumericMatches

boolean. Default value: false. Whether numeric placeholders must match numbers.

requireVariableMatches

boolean. Default value: false. Whether variable placeholders must match variables.

simplifyOnCompare

keyword. Level of simplification applied to math expressions before comparing.

Value	Description
`none` (default)	No simplification is applied before comparing.
`full`	Fully simplify both expressions before comparing.
`numbers`	Simplify numeric subexpressions only, leaving symbolic structure intact.
`numbersPreserveOrder`	Like `numbers`, but does not reorder commutative operands.
`normalizeOrder`	Reorder commutative operands into a canonical form without simplifying values.

symbolicEquality

boolean. Default value: false. Whether children compared via this boolean use symbolic equality.

unorderedCompare

boolean. Default value: false. Whether order is ignored when comparing list-like values.

Common to all components (9)

copy

reference. Create an independent copy of another component by reference. Enter a references a $name.

disabled

boolean. Default value: false. Whether this component is disabled and cannot be interacted with.

extend

reference. Extend another component by reference, inheriting its children and attributes. Enter a reference as $name.

fixed

boolean. Default value: false. Whether this component's value is fixed and cannot be modified.

fixLocation

boolean. Default value: false. Whether this component's location is fixed (preventing it from being moved while still allowing other modifications).

hide

boolean. Default value: false. Whether to hide this component from the rendered output.

isResponse

boolean. Default value: false. Whether this component is treated as a response for the purposes of assessment.

name

text. The name used to reference this component from elsewhere in the document.

styleNumber

integer. Default value: 1. The style number used to select this component's visual styling from the available style definitions.

Properties for `<matchesPattern name="m">`

Other (26)

$m.allowedErrorInNumbers

number. Maximum allowed numeric error when comparing numbers.

$m.allowedErrorIsAbsolute

boolean. Whether allowedErrorInNumbers is interpreted as an absolute (rather than relative) tolerance.

$m.allowImplicitIdentities

boolean. Whether to allow implicit identity transformations when matching.

$m.allowPermutations

boolean. Whether to allow permutations of operands when matching.

$m.caseInsensitiveMatch

boolean. Whether text comparisons ignore letter case.

$m.disabled

boolean. Whether this component is disabled and cannot be interacted with.

$m.excludeMatches

mathList. Patterns whose matches are excluded.

$m.expandOnCompare

boolean. Whether to expand math expressions before comparing.

$m.fixed

boolean. Whether this component's value is fixed and cannot be modified.

$m.fixLocation

boolean. Whether this component's location is fixed (preventing it from being moved while still allowing other modifications).

$m.hidden

boolean. Whether this component is hidden from the rendered output.

$m.includeErrorInNumberExponents

boolean. Whether the allowed numeric error also applies to numbers in exponents.

$m.matchBlanks

boolean. Whether unfilled blanks in a math expression count as a match.

$m.matchByExactPositions

boolean. Whether to match list values by exact position rather than by content.

$m.matchExpressionWithBlanks

boolean. Whether to allow expressions with blanks to match.

$m.numMatches

number. The number of matches found.

$m.numPeriodicSetMatchesRequired

integer. Number of consecutive elements of a periodic set required to count as a match.

$m.numSignErrorsMatched

number. Maximum number of sign errors that still count as a match.

$m.patternMatches

[ math ]. The list of matched sub-expressions.

$m.requireNumericMatches

boolean. Whether numeric placeholders must match numbers.

$m.requireVariableMatches

boolean. Whether variable placeholders must match variables.

$m.simplifyOnCompare

text. Level of simplification applied to math expressions before comparing.

$m.symbolicEquality

boolean. Whether children compared via this boolean use symbolic equality.

$m.text

text. The boolean rendered as a text string ("true" or "false").

$m.unorderedCompare

boolean. Whether order is ignored when comparing list-like values.

$m.value

boolean. Whether the input matches the pattern.

Common to all components (4)

$m.doenetML

text. The DoenetML source code that produced this component.

$m.hide

boolean. Whether to hide this component from the rendered output.

$m.isResponse

boolean. Whether this component is treated as a response for the purposes of assessment.

$m.styleNumber

integer. The style number used to select this component's visual styling from the available style definitions.

Examples

Example: Default case

The <matchesPattern> component is used to check that the user has supplied an equation in the requested format. The pattern attribute is required. If used without additional attributes as shown above, a rather liberal comparison occurs.

there must be two operands on one side, and none on the other
one side must contain only $y$ (RHS or LHS are acceptable)
the operands may be + or -

These requirements may be tightened, if desired, by applying additional attributes to <matchesPattern>.

Example: Match a specific form of linear equation

In this example, the following conditions must be met:

a $y$ by itself on one side, and an $x$ on the other, and no other variables can be present
the $x$ value must have a numerical coefficient, or no coefficient
switching the order of terms on the right-hand side is acceptable

The attribute requireNumericMatches ensures that the user only enters numerical coefficients into the ( ) spaces (rather than an x, for example.). Multiple <award> conditions are used to ensure that the case where $x$ does not have a coefficient are allowed.

m math (Page 1)

<matchesPattern>