s_test_case(validate_underscore(1+a_1), "Underscore characters are not permitted in this input.");
s_test_case(validate_underscore(1+a_1), "Underscore characters are not permitted in this input.");
/* The student may not use a user-defined function, or arrays, anywhere in their input. */
/* The student may not use a user-defined function, or arrays, anywhere in their input. */
validate_nofunctions(ex):= block([op1],
validate_nofunctions(ex):= block([op1],
if atom(ex) then return(""),
if atom(ex) then return(""),
op1:ev(op(ex)),
op1:ev(op(ex)),
...
@@ -49,3 +48,12 @@ s_test_case(validate_nofunctions(x(2)), "User-defined functions are not permitte
...
@@ -49,3 +48,12 @@ s_test_case(validate_nofunctions(x(2)), "User-defined functions are not permitte
s_test_case(validate_nofunctions(x(t)), "User-defined functions are not permitted in this input.");
s_test_case(validate_nofunctions(x(t)), "User-defined functions are not permitted in this input.");
s_test_case(validate_nofunctions(1+f(x+1)), "User-defined functions are not permitted in this input.");
s_test_case(validate_nofunctions(1+f(x+1)), "User-defined functions are not permitted in this input.");
/* The student may only use single-character variable names in their answer. */
/* This is intended for use when Insert Stars is turned off, but we still want to indicate to students that they may have forgotten a star */
validate_all_one_letter_variables(ex) := if not(is(ev(lmax(map(lambda([ex2],slength(string(ex2))),listofvars(ex))),simp)>1)) then ""
else "Only single-character variable names are permitted in this input. Perhaps you forgot to use an asterisk (*) somewhere, or perhaps you used a Greek letter.";
s_test_case(validate_all_one_letter_variables((Ax+B)/(x^2+1) + C/x), "Only single-character variable names are permitted in this input. Perhaps you forgot to use an asterisk (*) somewhere, or perhaps you used a Greek letter.");
s_test_case(validate_all_one_letter_variables((theta*x+B)/(x^2+1) + C/x), "Only single-character variable names are permitted in this input. Perhaps you forgot to use an asterisk (*) somewhere, or perhaps you used a Greek letter.");