`<extractMath>`

<extractMath> is a General Operator component that extracts data from mathematical expresssions. (See also, the <matchesPattern> component for an alternative method for extracting data.)

The types of data that can be extracted with <extractMath> are:

the number of operands in the expression
the individual operands themselves
the functions involved in an expression
the function arguments

Attributes and Properties

Attributes for `<extractMath>`
Attribute	Type	Values
`anchor = "…"`	point
`argumentNumber = "…"`	number
`createIntervals = "…"`	boolean	`"true"` `"false"`
`createVectors = "…"`	boolean	`"true"` `"false"`
`displayBlanks = "…"`	boolean	`"true"` `"false"`
`displayDecimals = "…"`	integer
`displayDigits = "…"`	integer
`displaySmallAsZero = "…"`	number
`draggable = "…"`	boolean	`"true"` `"false"`
`expand = "…"`	boolean	`"true"` `"false"`
`format = "…"`	text	`"text"` `"latex"`
`functionSymbols = "…"`	textList
`layer = "…"`	number
`operandNumber = "…"`	number
`padZeros = "…"`	boolean	`"true"` `"false"`
`parseScientificNotation = "…"`	boolean	`"true"` `"false"`
`positionFromAnchor = "…"`	text	`"upperright"` `"upperleft"` `"lowerright"` `"lowerleft"` `"top"` `"bottom"` `"left"` `"right"` `"center"`
`referencesAreFunctionSymbols = "…"`
`renderMode = "…"`	text
`simplify = "…"`	text	`"none"` `"full"` `"numbers"` `"numberspreserveorder"`
`splitSymbols = "…"`	boolean	`"true"` `"false"`
`type = "…"`		`"operand"` `"function"` `"functionargument"` `"numoperands"` `"recursiveoperands"`
`unordered = "…"`	boolean	`"true"` `"false"`

Props for `<extractMath name="e">`
Property	Type
`$e.anchor`	point
`$e.argumentNumber`	number
`$e.backgroundColor`	text
`$e.createIntervals`	boolean
`$e.createVectors`	boolean
`$e.disabled`	boolean
`$e.displayBlanks`	boolean
`$e.displayDecimals`	integer
`$e.displayDigits`	integer
`$e.displaySmallAsZero`	number
`$e.draggable`	boolean
`$e.expand`	boolean
`$e.fixed`	boolean
`$e.fixLocation`	boolean
`$e.format`	text
`$e.functionSymbols`	textList
`$e.hidden`	boolean
`$e.isNumber`	boolean
`$e.isNumeric`	boolean
`$e.latex`	latex
`$e.layer`	number
`$e.list`	[ math ]
`$e.matrix`	[ math ]
`$e.matrixSize`	numberList
`$e.number`	number
`$e.numColumns`	integer
`$e.numDimensions`	integer
`$e.numListItems`	integer
`$e.numRows`	integer
`$e.operandNumber`	number
`$e.padZeros`	boolean
`$e.parseScientificNotation`	boolean
`$e.positionFromAnchor`	text
`$e.renderMode`	text
`$e.simplify`	text
`$e.splitSymbols`	boolean
`$e.text`	text
`$e.textColor`	text
`$e.textStyleDescription`	text
`$e.unordered`	boolean
`$e.value`	extractMath
`$e.vector`	[ math ]
`$e.x`	math
`$e.y`	math
`$e.z`	math

Example: Extracting operands and number of operands

To extract an operand, you must also specify the operandNumber.

Example: Extracting functions and function arguments

To extract a function or functionArgument, you must first extract the operand under consideration. In order to extract an individual functionArgument in the case of a multivariable function; the argumentNumber must be provided as well.

Note that Doenet recognizes $f$ and $g$ as function symbols by default. If other symbols are to represent functions, they can be defined within the <math> component using the functionSymbols attribute.

Attribute Example: type

The type attribute specifies the value to be extracted; it takes one of four possible inputs: operand, numOperands, function, and functionArgument.

Attribute Example: operandNumber

The operandNumber attribute is necessary when the operand type is extracted. It specifies the location of the requested operand within the expression.

Attribute Example: argumentNumber

When function arguments are extracted from a math expression, the argumentNumber attribute specifies the location of the requested argument.

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