<answer>

Attribute Examples Part 2

The following examples illustrate use of the <answer> tag attributes.

Attributes

Example: maxNumAttempts

<m>\sqrt{529} = </m> 
  <answer maxNumAttempts="2" symbolicEquality>23</answer>

The maxNumAttempts attribute may be used to limit the number of attempts on a question-by-question basis.

Example: allowedErrorInNumbers

<p>Enter a number within about <m>1\%</m> of <m>100</m>: 
  <answer allowedErrorInNumbers="0.01">100</answer>
</p>
<p>Enter a number within 0.01 of <m>100</m>: 
  <answer allowedErrorInNumbers="0.01" allowedErrorIsAbsolute>100</answer>
</p>
<p>Enter an expression close to <m>\sin(\pi x)</m>: 
  <answer allowedErrorInNumbers="0.1" symbolicEquality>sin(pi x)</answer>
</p>

The allowedErrorInNumbers attribute may be used to specify a tolerance on numerical values that are considered to be correct. If the answer includes variables as well as numbers, using the symbolicEquality attribute will typically give more precise behavior.

By default, the error tolerance is specified as a fraction of the absolute value of the correct response.

The allowedErrorIsAbsolute attribute will change the tolerance to be specified as an absolute number.

Example: allowedErrorIsAbsolute

<p>Enter a number within <m>1</m> of <m>100</m>: 
  <answer allowedErrorInNumbers="1" allowedErrorIsAbsolute>100</answer></p>
 
<p>Enter a number within <m>10</m> of <m>100</m>: 
  <answer allowedErrorInNumbers="10" allowedErrorIsAbsolute>100</answer></p>

To specify an allowed error with a specific numerical value (rather than as a fraction of the correct response), use the allowedErrorIsAbsolute attribute in combination with the allowedErrorInNumbers attribute.

Example: includeErrorInNumberExponents

  <p>Allow a 1% error in <m>2x^3+4</m>, but only in the coefficient 2 and constant 4: 
  <answer allowedErrorInNumbers="0.01" symbolicEquality>2x^3+4</answer>
  </p>
 
    <p>Allow a 1% error in <m>2x^3+4</m>, in any of the 3 numbers: 
  <answer allowedErrorInNumbers="0.01" symbolicEquality includeErrorInNumberExponents>2x^3+4</answer>
  </p>

By default, allowedErrorInNumbers does not apply to exponents so that $x^{2.01}$ is not considered within 1% of $x^2$. To allow error in such exponents, add the includeErrorInNumberExponents attribute, preferably with the symbolicEquality attribute.

Example: caseInsensitiveMatch

<p>Enter tTkLp: <answer type="text">tTkLp</answer></p>
<p>Enter tTkLp with any capitalization: 
  <answer type="text" caseInsensitiveMatch>ttklp</answer>
</p>
 
<p>Either <m>x^2</m> or <m>X^2</m> is acceptable:
  <answer caseInsensitiveMatch>x^2</answer>
</p>

Use the caseInsensitiveMatch attribute if capitalization is not relevant for validation.

Example: showCorrectness

<m>\sqrt{529} = </m> 
  <answer name="ans1" showCorrectness="false" symbolicEquality>23</answer> 
 
<p>(Though it generally wouldn't make sense to show the credit 
if you're hiding correctness, you <em>could</em> 
show the credit achieved: $ans1.creditAchieved.)</p>
 
<p>Try again with a big button</p>
  <m>\sqrt{529} = </m> 
<answer 
  name="ans2" 
  showCorrectness="false" 
  symbolicEquality 
  forceFullCheckworkButton>
    23
</answer> 
 
<p>Customize message</p>
  <m>\sqrt{529} = </m> 
  
<answer name="ans3" 
  showCorrectness="false" 
  symbolicEquality 
  forceFullCheckworkButton 
  submitLabelNoCorrectness="submit!"
  >23
</answer> 

The showCorrectness attribute may be used to hide the validation of individual questions for assessments.

The default behavior is to show correctness unless either the handGraded attribute was specified or we are in assignment where the Show Correctness setting has been set to false.
The showCorrectness attribute on <answer> will override these settings to either always show or never show correctness.

Example: type=“text”

<p>Enter <em>hello</em>: <answer type="text">hello</answer></p>

The type attribute of <answer> is needed in a few cases to switch the answer to text mode when it cannot be inferred. In text mode, the response must match exactly with only whitespace difference at the beginning or end. See caseInsensitiveMatch for one way to relax this requirement.

Example: disableAfterCorrect

<p>Given an angle <m>\theta</m> on the unit circle, what 
is the name for the ratio of the opposite side to the hypotenuse?
<answer disableAfterCorrect>
  <choiceInput>
    <choice><m>\tan(\theta)</m></choice>
    <choice credit="1"><m>\sin(\theta)</m></choice>
    <choice><m>\cos(\theta)</m></choice>
    <choice><m>\cot(\theta)</m></choice>
  </choiceInput>
</answer></p>

The disableAfterCorrect attribute can be used to render <answer> components disabled after credit is achieved.

Example: submitLabel

<p>Move the point.</p>
<graph size="small">
  <point name="p"/>
</graph>
 
<answer submitLabel="Check Point">
  <award><when>$p != (0,0)</when></award>
</answer>

The submitLabel attribute can be used to create a custom label for the “Check Work” button.

Example: submitLabelNoCorrectness

<p>Move the point.</p>
<graph size="small">
  <point name="p"/>
</graph>
 
<answer submitLabelNoCorrectness="Submit Point" showCorrectness="false">
  <award><when>$p != (0,0)</when></award>
</answer>

The submitLabelNoCorrectness attribute modifies the standard “Submit Response” button label for answers where it is not desired to show correctness.

Example: selectMultiple

<p>Select all the warm colors:
  <answer matchPartial selectMultiple>
    <choice credit="1">yellow</choice>
    <choice>green</choice>
    <choice credit="1">orange</choice>
    <choice credit="1">red</choice>
    <choice>blue</choice>
  </answer>
</p>

The selectMultiple attribute allows multiple <choice> components to be selected for response.

Example: shuffleOrder

<p>Select the smallest number</p>
<answer shuffleOrder>
  <choice credit="1">1</choice>
  <choice>2</choice>
  <choice>3</choice>
  <choice>4</choice>
  <choice>5</choice>
</answer>

The shuffleOrder will create different variants of the document with the choices rendered in different orders.

Due to the algorithm used to generate these variants, the displayed variant may display the choices in the original order if there are fewer than 5 choices.

Example: splitSymbols

<p>Enter the product of the variables <c>two</c> and <c>vars</c>:
<answer splitSymbols="false">
  <math splitSymbols="false">two vars</math>
</answer>
</p>

By default, an <answer> will split multiple characters entered into the product of single character variables (unless the combination contains a non-leading number).
Setting splitSymbols to false will turn off this splitting so that variables in a product must be separated by a space or a multiplication symbol.

Example: expanded

<p>In one sentence, describe the theme of the story: 
  <answer name="ans" type="text" handGraded expanded/>
</p>

The expanded attribute renders an expanded text box for answers with type="text".

Example: displayDigitsForResponses

<p>Enter the value of <m>\pi</m> to at least 2 decimal places.
  <answer name="ans" 
    displayDigitsForResponses="5" 
    symbolicEquality 
    allowedErrorInNumbers="0.005" 
    allowedErrorIsAbsolute
    >3.141592653589793
  </answer>
</p>
<p>Your response: $ans</p>

The displayDigitsForResponses determines how many digits are displayed when referencing the users responses of the answer.

The default value is 10 digits.

Example: displayDigitsForCreditAchieved

The displayDigitsForCreditAchieved determines how many digits are displayed when referencing the creditAchieved property of the answer.

The default value is 3 digits.

Example: matchBlanks

<p>Enter <m>f()</m> with no arguments.
  <answer name="ans" matchBlanks>f()</answer>
</p>

If a mathematical expression is incomplete, such as <math>3+()</math>, it may contain blanks that are rendered by an underscore or a gray square. Since such blanks typically indicate an error in a mathematical expression, any expression with a blank will, by default, never match a correct answer.
To valid as correct a response that includes a blank, add the matchBlanks attribute to the <answer>.