def hint_check_function_used(ans, term):
'''
ans = student answer
term = search term to look for
search for function used in ans
don not worry about errors: those are caught by the caller
'''
case_sensitive = True
# parse expression
math_interpreter = ParseAugmenter(ans, case_sensitive)
math_interpreter.parse_algebra()
found = term in math_interpreter.functions_used
# for debugging
# print 'for %s, found=%s, variables = %s' % (ans, found, math_interpreter.variables_used)
return found
def hint_check_function_used(ans, term):
'''
ans = student answer
term = search term to look for
search for function used in ans
don not worry about errors: those are caught by the caller
'''
case_sensitive = True
# parse expression
math_interpreter = ParseAugmenter(ans, case_sensitive)
math_interpreter.parse_algebra()
found = term in math_interpreter.functions_used
# for debugging
# print 'for %s, found=%s, variables = %s' % (ans, found, math_interpreter.variables_used)
return found
def latex_preview(math_expr, variables=(), functions=(), case_sensitive=False):
"""
Convert `math_expr` into latex, guaranteeing its parse-ability.
Analagous to `evaluator`.
"""
# No need to go further
if math_expr.strip() == "":
return ""
# Parse tree
latex_interpreter = ParseAugmenter(math_expr, case_sensitive)
latex_interpreter.parse_algebra()
# Get our variables together.
variables, functions = add_defaults(variables, functions, case_sensitive)
# Create a recursion to evaluate the tree.
if case_sensitive:
casify = lambda x: x
else:
casify = lambda x: x.lower() # Lowercase for case insens.
render_actions = {
'number': render_number,
'variable': variable_closure(variables, casify),
'function': function_closure(functions, casify),
'atom': render_atom,
'power': render_power,
'parallel': render_parallel,
'product': render_product,
'sum': render_sum
}
backslash = "\\"
wrap_escaped_strings = lambda s: LatexRendered(
s.replace(backslash, backslash * 2)
)
output = latex_interpreter.reduce_tree(
render_actions,
terminal_converter=wrap_escaped_strings
)
return output.latex
