As a follow-up, I've isolated the problem to the rendering of the ijk format of the vector. A stripped down version of the problem that I'm using is appended. In this, both ijk formatted vectors display as in the lower figure above (as an experiment, I also moved the definition of `$vijk`

above the `Context()->texStrings`

call, to no effect); the standard formatted vector is as expected; and the components of the vector all display correctly.

Thoughts welcome. Thanks,

Gavin

DOCUMENT(); loadMacros( "PGstandard.pl", "MathObjects.pl", ); TEXT(beginproblem()); $showPartialCorrectAnswers = 1; $c1 = non_zero_random(-5,5,1); $c2 = non_zero_random(3,7,1); $c3 = non_zero_random(-3,3,1); $c1c2 = $c1*$c2; $twoc1 = 2*$c1; $c2m1 = $c2 - 1; $nc1c2 = -1*$c1c2; Context('Vector')->variables->add('t'=>'Real'); @vel = ( Compute("($twoc1)*t+$c2"), Compute("-$c1*e^(-t)"), Compute("-($c1c2)*sin($c2*t)") ); $vel = Vector( @vel ); $acc = $vel->D; Context()->texStrings; $vijk = $vel->ijk; BEGIN_TEXT The velocity of a particle is given by \( {\bf v}(t) = \{ $vel->ijk \} \). Find the acceleration \( {\bf a}(t) \): \{ ans_rule(45) \} $PAR \(v_1 = $vel[0] \)$BR \(v_2 = $vel[1] \)$BR \(v_3 = $vel[2] \)$BR \(v = $vel \)$BR \(v = $vijk\) END_TEXT ANS( $acc->cmp() ); ENDDOCUMENT();