suvat_calculator.py

import streamlit as st
import math
from htbuilder import HtmlElement, div, ul, li, br, hr, a, p, img, styles, classes, fonts
from htbuilder.units import percent, px
from htbuilder.funcs import rgba, rgb

#############
# Functions #
#############

def _ask(variable):
    return st.number_input(f'{variable} :', step=None, format='%f')

def ask(*variables):                    #  https://codereview.stackexchange.com/a/259470/230104
    return [_ask(variable) for variable in variables]

def check_variables(variables, values):    #  https://codereview.stackexchange.com/a/259505/230104
    for variable, flag in variables.items():
        if flag != (variable in values):
            return False
    return True

##########
# Styles #
##########

primaryColor = st.get_option("theme.primaryColor")
s = f"""
<style>
@import url('https://fonts.googleapis.com/css2?family=Atma:wght@600&display=swap');
div.stButton > button:first-child {{ border: 5px solid {primaryColor}; border-radius:20px 20px 20px 20px; }}
<style>
"""
st.markdown(s, unsafe_allow_html=True)

##############
# Dictionary #
##############

strings = {
  'বাংলা': {
    'title': f"<div><h1 style='text-align: center; color: {primaryColor}; font-family: Atma'> গতি-সমীকরণ ক্যালকুলেটর </h1></div>",
    'about': 'নিউটনিয়ান গতি-সমীকরণগুলো (SUVAT সমীকরণ) দিয়ে সমত্বরণে চলমান বস্তুর গতীয় চলকগুলো হিসাব করতে এই ক্যালকুলেটরটি আপনাকে সাহায্য করবে।',
    'select': 'যে চলক তিনটির মান আপনি জানেন, তাদেরকে নির্বাচন করুন:',
    's': 'সরণ',
    'u': 'আদিবেগ',
    'v': 'শেষবেগ',
    'a': 'ত্বরণ',
    't': 'সময়',
    'min3': 'কমপক্ষে যেকোন তিনটি চলক নির্বাচন করুন যাদের মান আপনার জানা আছে।',
    'insert': 'আপনার নির্বাচিত ৩টা চলকের মান একই ইউনিট সিস্টেমে লিখুন। সেই অনুযায়ী এই ক্যালকুলেটর বাকি ২টা চলকের মান হিসাব করে জানিয়ে দিবে।',
    'max3': 'সর্ব্বোচ্চ যেকোন তিনটি চলক নির্বাচন করুন যাদের মান আপনার জানা আছে।',
    'button': 'বাকি দুই চলকের অজানা মান সমীকরণসহ জানতে এখানে ক্লিক করুন',
    'eqns': 'মান নির্ণয়ে ব্যবহৃত সমীকরণদ্বয়:\n',
    'here': 'এখানে',
    'notallow': 'বসালে চলবে না।',
    'inserting': 'আপনার দেওয়া মানগুলো উক্ত সমীকরণদ্বয়ে বসিয়ে পাই:',
  },
  'English': {
    'title': f"<div><h1 style='text-align: center; color: {primaryColor}; font-family: Atma'> Motion-Equation Calculator </h1></div>",
    'about': 'This calculator app will help to calculate the variables of the Newtonian equations of linear motion aka SUVAT equations.',
    'select': 'Select any 3 known-valued variables:',
    's': 'Displacement',
    'u': 'Initial Velocity',
    'v': 'Final Velocity',
    'a': 'Acceleration',
    't': 'Time',
    'min3': 'Select at least 3 variables.',
    'insert': 'Enter their values in the same unit system. Accordingly, this calculator will return the values of the remaining 2 variables.',
    'max3': 'Select only 3 variables.',
    'button': 'Click here to get the values of the rest two variables with equations',
    'eqns': 'The equations which are used to determine the values:\n',
    'here': 'Here',
    'notallow': 'is not allowed.',
    'inserting': 'Inserting your given values in these equations, we get:',
  }
}

############
# Main App #
############

def app(strs):
    st.markdown(strs['title'], unsafe_allow_html=True)
    st.write(strs['about'])
    st.write(strs['select'])
    opts = [ ('s', strs['s']), ('u', strs['u']), ('v', strs['v']), ('a', strs['a']), ('t', strs['t']) ]
    known_variables = {symbol: st.checkbox(f"{name} ({symbol})") for symbol, name in opts}    # https://codereview.stackexchange.com/a/259472/230104

    if sum(known_variables.values()) <3:
        st.write(strs['min3'])
    elif sum(known_variables.values()) == 3:
        st.write(strs['insert'])
    else:
        st.write(strs['max3'])

    if check_variables(known_variables, ['u', 'v', 't']):    # [u, v, t]
        u, v, t = ask(strs['u']+' (u)', strs['v']+' (v)', strs['t']+' (t)')
        if st.button(strs['button']) is True:
            st.write(strs['eqns'] +
            '$$\n' +
            's = \\frac{1}{2}(u+v)t, \\quad a = \\frac{v-u}{t}' +
            '\n$$')
            s = 0.5*(u+v)*t
            try:
                a = (v-u)/t
            except ZeroDivisionError:
                st.write(strs['here']+' $t=0$ '+strs['notallow'])
                a = None
            st.write(strs['inserting'])
            st.write(strs['s']+' $(s) = \\frac{1}{2}(u+v)t =$ ', s)
            st.write(strs['a']+' $(a) = \\frac{v-u}{t} =$ ', a)

    elif check_variables(known_variables, ['u', 'v', 'a']):  # [u, v, a]
        u, v, a = ask(strs['u']+' (u)', strs['v']+' (v)',  strs['a']+' (a)')
        if st.button(strs['button']) is True:
            st.write(strs['eqns'] +
            '$$\n' +
            's = \\frac{v^2-u^2}{2a}, \\quad t = \\frac{v-u}{a}' +
            '\n$$')
            try:
                s = (v*v - u*u)/(2*a)
                t = (v - u)/a
            except ZeroDivisionError:
                st.write(strs['here']+' $a=0$ '+strs['notallow'])
                s = None
                t = None
            st.write(strs['inserting'])
            st.write( strs['s']+' $(s) = \\frac{v^2-u^2}{2a} =$ ', s)
            st.write( strs['t']+' $(t) = \\frac{v-u}{a} =$ ', t)

    elif check_variables(known_variables, ['u', 'a', 't']): # [u, a, t]
        u, a, t = ask(strs['u']+' (u)',  strs['a']+' (a)',  strs['t']+' (t)')
        if st.button(strs['button']) is True:
            st.write(strs['eqns'] +
            '$$\n' +
            's = ut + \\frac{1}{2}at^2, \\quad v = u + at' +
            '\n$$')
            s = u*t + 0.5*a*t*t
            v = u + a*t
            st.write(strs['inserting'])
            st.write( strs['s']+' $(s) = ut + \\frac{1}{2}at^2 =$ ', s)
            st.write( strs['v']+' $(v) = u + at =$ ', v)

    elif check_variables(known_variables, ['v', 'a', 't']):  # [v, a, t]
        v, a, t = ask(strs['v']+' (v)',  strs['a']+' (a)',  strs['t']+' (t)')
        if st.button(strs['button']) is True:
            st.write(strs['eqns'] +
            '$$\n' +
            's = vt - \\frac{1}{2}at^2, \\quad u= v - at' +
            '\n$$')
            s = v*t - 0.5*a*t*t
            u = v - a*t
            st.write(strs['inserting'])
            st.write( strs['s']+' $(s) = vt - \\frac{1}{2}at^2 =$ ', s)
            st.write( strs['u']+' $(u) = v - at =$ ', u)

    elif check_variables(known_variables, ['s', 'a', 't']):  # [s, a, t]
        s, a, t = ask( strs['s']+' (s)',  strs['a']+' (a)',  strs['t']+' (t)')
        if st.button(strs['button']) is True:
            st.write(strs['eqns'] +
            '$$\n' +
            'u = \\frac{s}{t} - \\frac{1}{2}at, \\quad v = \\frac{s}{t} + \\frac{1}{2}at' +
            '\n$$')
            try:
                u = (s - 0.5*a*t*t)/t
                v = (s + 0.5*a*t*t)/t
            except ZeroDivisionError:
                st.write(strs['here']+' $t=0$ '+strs['notallow'])
                u = None
                v = None
            st.write(strs['inserting'])
            st.write( strs['u']+' $(u) = \\frac{s}{t} - \\frac{1}{2}at =$ ', u)
            st.write( strs['v']+' $(v) = \\frac{s}{t} + \\frac{1}{2}at =$ ', v)

    elif check_variables(known_variables, ['s', 'v', 't']):  # [s, v, t]
        s, v, t = ask( strs['s']+' (s)', strs['v']+' (v)',  strs['t']+' (t)')
        if st.button(strs['button']) is True:
            st.write(strs['eqns'] +
            '$$\n' +
            'u = \\frac{2s}{t} - v, \\quad a = \\frac{2(vt-s)}{t^2}' +
            '\n$$')
            try:
                u = (2*s)/t - v
                a = 2*(v*t-s)/(t*t)
            except ZeroDivisionError:
                st.write(strs['here']+' $t=0$ '+strs['notallow'])
                u = None
                a = None
            st.write(strs['inserting'])
            st.write( strs['u']+' $(u) = \\frac{2s}{t} - v =$ ', u)
            st.write( strs['a']+' $(a)  = \\frac{2(vt-s)}{t^2} =$ ', a)

    elif check_variables(known_variables, ['s', 'v', 'a']):  # [s, v, a]
        s, v, a = ask( strs['s']+' (s)', strs['v']+' (v)',  strs['a']+' (a)')
        if st.button(strs['button']) is True:
            st.write(strs['eqns'] +
            '$$\n' +
            'u = \\sqrt{v^2 -2as}, \\quad t = \\frac{v}{a} - \\frac{\\sqrt{v^2 - 2as}}{a}' +
            '\n$$')
            try:
                u = math.sqrt(v*v - 2*a*s)
                t = v/a - math.sqrt(v*v - 2*a*s)/a
            except ZeroDivisionError:
                st.write(strs['here']+' $a=0$ '+strs['notallow'])
                t = None
            except ValueError:
                st.write(strs['here']+' $v^2 < 2as$ '+strs['notallow'])
                u = None
                t = None
            st.write(strs['inserting'])
            st.write( strs['u']+' $(u) = \\sqrt{v^2 -2as} =$ ', u)
            st.write( strs['t']+'  $(t)= \\frac{v}{a} - \\frac{\\sqrt{v^2 - 2as}}{a} =$ ', t)

    elif check_variables(known_variables, ['s', 'u', 't']):  # [s, u, t]
        s, u, t = ask( strs['s']+' (s)', strs['u']+' (u)',  strs['t']+' (t)')
        if st.button(strs['button']) is True:
            st.write(strs['eqns'] +
            '$$\n' +
            'v = \\frac{2s}{t}-u, \\quad a = \\frac{2(s-ut)}{t^2}' +
            '\n$$')
            try:
                v = (2*s)/t - u
                a = 2*(s-u*t)/(t*t)
            except ZeroDivisionError:
                st.write(strs['here']+' $t=0$ '+strs['notallow'])
                v = None
                a = None
            st.write(strs['inserting'])
            st.write( strs['v']+' $(v) = \\frac{2s}{t}-u =$ ', v)
            st.write( strs['a']+' $(a)= \\frac{2(s-ut)}{t^2} =$ ', a)

    elif check_variables(known_variables, ['s', 'u', 'a']):  # [s, u, a]
        s, u, a = ask( strs['s']+' (s)', strs['u']+' (u)',  strs['a']+' (a)')
        if st.button(strs['button']) is True:
            st.write(strs['eqns'] +
            '$$\n' +
            'v = \\sqrt{u^2 + 2as}, \\quad t = -\\frac{u}{a} + \\frac{\\sqrt{u^2 + 2as}}{a}' +
            '\n$$')
            try:
                v = math.sqrt(u*u + 2*a*s)
                t = -u/a + math.sqrt(u*u +2*a*s)/a
            except ZeroDivisionError:
                st.write(strs['here']+' $a=0$ '+strs['notallow'])
                t = None
            except ValueError:
                st.write(strs['here']+' $v^2 < 2as$ '+strs['notallow'])
                v = None
                t = None
            st.write(strs['inserting'])
            st.write( strs['v']+' $(v) = \\sqrt{u^2 + 2as} =$ ', v)
            st.write( strs['t']+' $(t) = -\\frac{u}{a} + \\frac{\\sqrt{u^2 + 2as}}{a} =$ ', t)

    elif check_variables(known_variables, ['s', 'u', 'v']):  # [s, u, v]
        s, u, v = ask( strs['s']+' (s)', strs['u']+' (u)', strs['v']+' (v)')
        if st.button(strs['button']) is True:
            st.write(strs['eqns'] +
            '$$\n' +
            'a = \\frac{v^2 - u^2}{2s}, \\quad t = \\frac{2s}{u+v}' +
            '\n$$')
            try:
                a = (v*v - u*u)/(2*s)
            except ZeroDivisionError:
                st.write(strs['here']+' $s=0$ '+strs['notallow'])
                a = None
            try:
                t = (2*s)/(u+v)
            except ZeroDivisionError:
                st.write(strs['here']+' $u+v=0$ '+strs['notallow'])
                t = None
            st.write(strs['inserting'])
            st.write( strs['a']+' $(a) = \\frac{v^2 - u^2}{2s} =$ ', a)
            st.write( strs['t']+' $(t) = \\frac{2s}{u+v} =$ ', t)

lang = st.sidebar.radio('Select Language:', ['বাংলা', 'English'], index=0)
app(strings[lang])

##########
# Footer #                         #  https://discuss.streamlit.io/t/st-footer/6447
##########

def image(src_as_string, **style):
    return img(src=src_as_string, style=styles(**style))

def link(link, text, **style):
    return a(_href=link, _target="_blank", style=styles(**style))(text)

def layout(*args):
    style = """
    <style>
        MainMenu {visibility: hidden;}
        footer {visibility: hidden;}
        .stApp { bottom: 60px; }
    </style>
    """

    style_div = styles(
        position="fixed",
        left=0,
        bottom=0,
        margin=px(0, 15, 0, 0),
        text_align="center",
        opacity=0.5,
    )

    body = p()
    foot = div(
        style=style_div
    )(
        body
    )

    st.markdown(style, unsafe_allow_html=True)
    for arg in args:
        if isinstance(arg, str):
            body(arg)
        elif isinstance(arg, HtmlElement):
            body(arg)
    st.markdown(str(foot), unsafe_allow_html=True)

def footer():
    myargs = [
        link("https://bigganblog.org/2021/03/গতির-সমীকরণ", image('https://raw.githubusercontent.com/rafisics/suvat_calculator/main/img/bigganblog_badge_black_white.png',)),
    ]
    layout(*myargs)

if __name__ == "__main__":
    footer()