Skip to content

pl-number-input element

Fill in the blank field that allows for numeric value input within specific tolerances.

Sample element

Screenshot of the pl-number-input element with relative tolerance

question.html
<pl-number-input answers-name="ans_rtol" label="$x =$"> </pl-number-input>
server.py
import random

def generate(data):

    # Generate a random value
    x = random.uniform(1, 2)

    # Answer to fill in the blank input
    data["correct_answers"]["ans_rtol"] = x

Screenshot of the pl-number-input element with sigfigs

question.html
<pl-number-input answers-name="ans_sig" comparison="sigfig" digits="2" label="$x =$">
</pl-number-input>
server.py
import random

def generate(data):

    # Generate a random value
    x = random.uniform(1, 2)

    # Answer to fill in the blank input
    data["correct_answers"]["ans_sig"] = round(x, 2)

Customizations

Attribute Type Default Description
allow-blank boolean false Whether an empty input box is allowed. By default, empty input boxes will not be graded (invalid format).
allow-complex boolean false Whether to allow complex numbers as answers. If the correct answer is set in server.py as a complex object, you should use import prairielearn as pl and data["correct_answers"][answers-name] = pl.to_json(ans).
allow-fractions boolean true Whether to allow answers expressed as a rational number of the format a/b.
answers-name string — Variable name to store data in. Note that this attribute has to be unique within a question, i.e., no value for this attribute should be repeated within a question.
aria-label string — An accessible label for the element.
atol number 1e-8 Absolute tolerance for comparison="relabs".
blank-value string 0 (zero) Value to be used as an answer if element is left blank. Only applied if allow-blank is true. Must be "" (empty string) or follow the same format as an expected user input (e.g., fractions if allowed, complex numbers if allowed, etc.).
comparison "relabs", "sigfig", or "decdig" "relabs" How to grade. "relabs" uses relative (rtol) and absolute (atol) tolerances. "sigfig" and "decdig" use digits significant or decimal digits.
correct-answer float See description Correct answer for grading. Defaults to data["correct_answers"][answers-name].
custom-format string See description Custom format to use when formatting the submitted or correct answer. By default, submitted answers are shown with the format ".12g", while the correct answer uses ".12g" if the comparison method is "relabs", or a custom format based on the number of digits if the comparison method is "sigfig" or "decdig". A full description of the format can be found on the Python documentation page.
digits integer 2 number of digits that must be correct for comparison="sigfig" or comparison="decdig".
display "block" or "inline" "inline" How to display the input field.
initial-value string — Initial value to prefill the input box the first time it is rendered.
label string — A prefix to display before the input box (e.g., label="$F =$").
placeholder string See description Custom placeholder text. By default, the placeholder text shown is the default comparison.
rtol number 1e-2 Relative tolerance for comparison="relabs".
show-correct-answer boolean true Whether to show the correct reference answer in the submission panel if the submitted answer was correct (i.e., within the specified tolerance).
show-help-text boolean true Show the question mark at the end of the input displaying required input parameters.
show-score boolean true Whether to show the score badge next to this element.
size integer 35 Size of the input box.
suffix string — A suffix to display after the input box (e.g., suffix="$\rm m/s^2$").
weight integer 1 Weight to use when computing a weighted average score over elements.

Example implementations

See also