utils.py

import re
INVALID_ANS = "[invalid]"


def normalize_float_string(input_string):
    res = input_string.replace(",", "").replace("$", "").replace("%", "")
    if res[-1] == ".":
        res = res[:-1]
    res = float(res)
    res = round(res, 3)
    res = str(res)

    return res


def extract_answer_gsm8k(input_string):
    ans_pattern = re.compile(r"#### (\-?[0-9\.\,]+)$")
    match = ans_pattern.search(input_string)
    try:
        if match:
            match_str = match.group(1).strip()
            match_str = normalize_float_string(match_str)
        elif "he answer is" in input_string:
            match_str = input_string.split("he answer is")[-1].strip()
            match_str = normalize_float_string(match_str)
        else:
            match_str = INVALID_ANS
    except:
        return INVALID_ANS

    return match_str


def _fix_fracs(string):
    substrs = string.split("\\frac")
    new_str = substrs[0]
    if len(substrs) > 1:
        substrs = substrs[1:]
        for substr in substrs:
            new_str += "\\frac"
            if len(substr) > 0 and substr[0] == "{":
                new_str += substr
            else:
                try:
                    assert len(substr) >= 2
                except:
                    return string
                a = substr[0]
                b = substr[1]
                if b != "{":
                    if len(substr) > 2:
                        post_substr = substr[2:]
                        new_str += "{" + a + "}{" + b + "}" + post_substr
                    else:
                        new_str += "{" + a + "}{" + b + "}"
                else:
                    if len(substr) > 2:
                        post_substr = substr[2:]
                        new_str += "{" + a + "}" + b + post_substr
                    else:
                        new_str += "{" + a + "}" + b
    string = new_str
    return string


def _fix_a_slash_b(string):
    if len(string.split("/")) != 2:
        return string
    a = string.split("/")[0]
    b = string.split("/")[1]
    try:
        if "sqrt" not in a:
            a = int(a)
        if "sqrt" not in b:
            b = int(b)
        assert string == "{}/{}".format(a, b)
        new_string = "\\frac{" + str(a) + "}{" + str(b) + "}"
        return new_string
    except:
        return string


def _fix_sqrt(string):
    _string = re.sub(r"\\sqrt(\w+)", r"\\sqrt{\1}", string)
    return _string


def strip_string(string):
    string = str(string).strip()
    # linebreaks
    string = string.replace("\n", "")

    # right "."
    string = string.rstrip(".")

    # remove inverse spaces
    string = string.replace("\\!", "")
    string = string.replace("\\ ", "")

    # replace \\ with \
    string = string.replace("\\\\", "\\")
    string = string.replace("\\\\", "\\")

    # replace tfrac and dfrac with frac
    string = string.replace("tfrac", "frac")
    string = string.replace("dfrac", "frac")

    # remove \left and \right
    string = string.replace("\\left", "")
    string = string.replace("\\right", "")

    # Remove unit: miles, dollars if after is not none
    _string = re.sub(r"\\text{.*?}$", "", string).strip()
    if _string != "" and _string != string:
        # print("Warning: unit not removed: '{}' -> '{}'".format(string, _string))
        string = _string

    # Remove circ (degrees)
    string = string.replace("^{\\circ}", "")
    string = string.replace("^\\circ", "")

    # remove dollar signs
    string = string.replace("\\$", "")
    string = string.replace("$", "")

    string = string.replace("\\text", "")
    string = string.replace("x\\in", "")

    # remove percentage
    string = string.replace("\\%", "")
    string = string.replace("\%", "")
    string = string.replace("%", "")

    # " 0." equivalent to " ." and "{0." equivalent to "{." Alternatively, add "0" if "." is the start of the string
    string = string.replace(" .", " 0.")
    string = string.replace("{.", "{0.")

    # cdot
    string = string.replace("\\cdot", "")

    # inf
    string = string.replace("infinity", "\\infty")
    if "\\infty" not in string:
        string = string.replace("inf", "\\infty")
    string = string.replace("+\\inity", "\\infty")

    # and 
    string = string.replace("and", "")
    string = string.replace("\\mathbf", "")

    # use regex to remove \mbox{...}
    string = re.sub(r"\\mbox{.*?}", "", string)

    # quote
    string.replace("'", "")
    string.replace("\"", "")
    
    # i, j
    if "j" in string and "i" not in string:
        string = string.replace("j", "i")

    # replace a.000b where b is not number or b is end, with ab, use regex
    string = re.sub(r"(\d+)\.0+([^\d])", r"\1\2", string)
    string = re.sub(r"(\d+)\.0+$", r"\1", string)

    # if empty, return empty string
    if len(string) == 0:
        return string
    if string[0] == ".":
        string = "0" + string

    # to consider: get rid of e.g. "k = " or "q = " at beginning
    if len(string.split("=")) == 2:
        if len(string.split("=")[0]) <= 2:
            string = string.split("=")[1]

    string = _fix_sqrt(string)
    string = string.replace(" ", "")

    # \frac1b or \frac12 --> \frac{1}{b} and \frac{1}{2}, etc. Even works with \frac1{72} (but not \frac{72}1). Also does a/b --> \\frac{a}{b}
    string = _fix_fracs(string)

    # NOTE: X/Y changed to \frac{X}{Y} in dataset, but in simple cases fix in case the model output is X/Y
    string = _fix_a_slash_b(string)

    return string

def extract_answer_math(pred_str):
    if 'boxed' in pred_str:
        ans = pred_str.split('boxed')[-1]
        if len(ans) == 0:
            return ""
        elif (ans[0] == '{'):
            stack = 1
            a = ''
            for c in ans[1:]:
                if (c == '{'):
                    stack += 1
                    a += c
                elif (c == '}'):
                    stack -= 1
                    if (stack == 0): break
                    a += c
                else:
                    a += c
        else:
            a = ans.split('$')[0].strip()
        pred=a
    elif ('he answer is' in pred_str):
        pred = pred_str.split('he answer is')[-1].strip()
    # elif extract_program_output(pred_str) != "":
    #     # fall back to program
    #     pred = extract_program_output(pred_str)
    else: # use the last number
        pattern = '-?\d*\.?\d+'
        pred = re.findall(pattern, pred_str.replace(",", ""))
        if(len(pred) >= 1):
            pred = pred[-1]
        else: pred = ''
    
    # multiple line
    pred = pred.split("\n")[0]
    if pred != "" and pred[0] == ":":
        pred = pred[1:]
    if pred != "" and pred[-1] == ".":
        pred = pred[:-1]
    if pred != "" and pred[-1] == "/":
        pred = pred[:-1]
    pred = strip_string(pred)
    return pred