## WeBWorK Problems

### Filling a table with Numeric and Point

by Teresa Adams -
Number of replies: 1
I am trying to build a table and the table has answers that are y-values, ordered pairs, and the secant of a line. I will be quite honest, I am really not sure what I am doing. This is what I have so far:

###########################
# Initialization

DOCUMENT();

"PGstandard.pl",
"MathObjects.pl",
"PGML.pl",
"PGcourse.pl",
"PGgraphmacros.pl",
"scaffold.pl",
"contextLimitedPoint.pl",
);

TEXT(beginproblem());
$showPartialCorrectAnswers = 1; ########################### # Setup #$x0 is the x-value in the ordered pairs P(x, y)
# $d is the vertical translation of the function #$y0 is the y-value in the ordered pairs P(x, y)
# $seq fills in the table values for x #$df is the derivative of the function
# $df_x0 is the derivative of the function evaluated at x0 #$answer[13] is the derivative of the function evaluated at x0
# $b is the y-intercept of the tangent line #$tanline is the equation of the line tangent at the point P(x, y)

Context("Numeric");
Context()->flags->set(tolerance => 0.01);
Context()->{format}{number} = "%.4f#";

$x0 = Real(1); @seq = (); foreach my$i (1..4) {
$seq[$i] = $x0+1/10**$i;
}

$d = random(-5, 5, 1);$f = Formula("x^2+$d");$y0 = $f->eval(x=>$x0);

$df =$f->D('x');

$df_x0=$df->eval(x=>$x0);$b=$y0-$df_x0*$x0;$tanline=Formula("$df_x0*x+$b");

for $i (0..11) { if ($i==(0, 9, 3)) {
$k=$i/3+1;
$answer[$i] = $f->eval(x=>$seq[$k]); } elsif ($i==(1, 10, 3)) {
Context("LimitedPoint");
$k=($i-1)/3+1;
$answer[$i]= Point("($seq[$k]","$answer[$k-1])");
} else {
Context("Numeric");
$k=($i-2)/3+1;
$deltay=$y0-$answer[$k-1]
$deltax=$x0-$seq[$k]
$answer[$i]=$deltay/$deltax;
}
}

$answer[13]=$df_x0;

$answer[14]=$tanline;

$table =$BCENTER.begintable(5) .
row( "x", "y", "Q(x,y)", "m_sec" ) .
row( "$seq[1]", ans_rule(8), ans_rule(8), ans_rule(8)). row("$seq[2]", ans_rule(8), ans_rule(8), ans_rule(8)).
row("$seq[3]", ans_rule(8), ans_rule(8), ans_rule(8)). row("$seq[4]", ans_rule(8), ans_rule(8), ans_rule(8)).
endtable().$ECENTER; ########################### # Main text Scaffold::Begin(); BEGIN_PGML The points [P([$x0],[$y0])] and [ Q(x,y)] are on the graph of the function [ f(x) = [$f] ]. Complete the table with the appropriate values for [y], [Q(x,y)], and the slope of the secant line passing through points [P] and [Q]. Round to four decimal places.

[@ $table @]*** END_PGML ############################ # Part 1 Answer evaluation for$i (0..11) {
ANS( $answer[$i]->cmp() );
}

###########################
# Part 2

Section::Begin("Part 2");

BEGIN_PGML

Using the values in the right column of the table, the estimated value of the slope of the line tangent to [f] at [x=[$x0]] is [_________] END_PGML ############################ # Part 2 Answer evaluation ANS($answer[13]->cmp());

Section::End();

###########################
# Part 3

Section::Begin("Part 3");

BEGIN_PGML

The equation of the tangent line at point [P] is [y=] [_________]

END_PGML

############################
# Part 3 Answer evaluation

Section::End();

Scaffold::End();

The error message I am getting is:
 Problem2 1. ERROR caught by Translator while processing problem file:02.1/CCD_CCCS_Openstax_Calc1_C1-2016- 002_02_1_sample.pg **************** ERRORS from evaluating PG file:
Compilation error
If someone could help me, I would greatly appreciate it.