import re
import rich
ratio_length = dict(inch2m=0.0254, inch2dm=0.254, inch2cm=2.54, inch2mm=25.4,
inch2km=2.54e-5, inch2ft=0.0833333333,
ft2mm=304.8, ft2cm=30.48, ft2dm=3.048, ft2m=0.3048, ft2km=3.048e-4,
mm2cm=0.1, mm2dm=0.01, mm2m=0.001, mm2km=1e-6,
cm2dm=0.1, cm2m=0.01, cm2km=1e-5, m2km=1e-3)
ratio_force = dict(lb2lbf=1, lb2kip=0.001, lb2n=4.4482216282509,
lb2kn=4.4482216282509e-3, lb2mn=4.448e-6,
lb2kgf=0.45359236844386, lb2tonf=0.0004535923699994,
lbf2kip=0.001, lbf2n=4.4482216282509,
lbf2kn=4.4482216282509e-3, lbf2mn=4.448e-6,
lbf2kgf=0.45359236844386, lbf2tonf=0.0004535923699994,
kip2n=4448.2216, kip2kn=4448.2216e-3, kip2mn=4448.2216e-6,
kip2kgf=453.59236844386, kip2tonf=0.4535923699994,
n2kn=1e-3, n2mn=1e-6, n2kgf=0.10197162129779283,
n2tonf=0.0001019716212978, kn2mn=1e-3, kn2kgf=101.9716212978,
kn2tonf=0.1019716212978, mn2kgf=101971.6212978,
mn2tonf=101.9716212978, kgf2tonf=0.001)
ratio_time = dict(sec2msec=0.001)
def ratio_update(ratio_dict):
temp_dict = dict()
for key, value in ratio_dict.items():
idx = key.index("2")
new_key = key[idx+1:] + "2" + key[:idx]
temp_dict[new_key] = 1 / value
new_key = key[:idx] + "2" + key[:idx]
temp_dict[new_key] = 1
ratio_dict.update(temp_dict)
ratio_update(ratio_length)
ratio_update(ratio_force)
ratio_update(ratio_time)
unit_length = ["inch", "ft", "mm", "cm", "m"]
unit_force = ["lb", "lbf", "kip", "n", "kn", "mn", "kgf", "tonf"]
unit_time = ["sec", "msec"]
unit_mass = ["mg", "g", "kg", "ton", "t", "slug"]
unit_stress = ["pa", "kpa", "mpa", "gpa", "bar", "psi", "ksi", "psf", "ksf"]
[docs]
class UnitSystem:
"""A class for unit conversion.
Parameters
-----------
length: str, default="m"
Length unit base. Optional ["inch", "ft", "mm", "cm", "m"].
force: str, default="kN"
Force unit base. Optional ["lb"("lbf"), "kip", "n", "kn", "mn", "kgf", "tonf"].
time: str, default="sec"
Time unit base. Optional ["sec", "msec"].
.. note::
* `Mass` and `stress` units can be automatically determined based on `length` and `force` units,
optional mass units include ["mg", "g", "kg", "ton"("t"), "slug"],
and optional stress units include ["pa", "kpa", "mpa", "gpa", "bar", "psi", "ksi", "psf", "ksf"].
* You can enter any uppercase and lowercase forms, such as ``kn`` and ``kN``, ``mpa`` and ``MPa``
are equivalent.
* You can add a number after the unit to indicate a power, such as ``m3`` for ``m*m*m``.
"""
def __init__(self,
length: str = "m",
force: str = "kn",
time: str = "sec") -> None:
for unit in unit_length:
setattr(self, unit, ratio_length[unit + "2" + length.lower()])
for unit in unit_force:
setattr(self, unit, ratio_force[unit + "2" + force.lower()])
for unit in unit_time:
setattr(self, unit, ratio_time[unit + "2" + time.lower()])
# mass
self.kg = self.n * self.sec**2 / self.m
self.mg, self.g, self.ton = 1e-6 * self.kg, 1e-3 * self.kg, 1e3 * self.kg
self.t, self.slug = 1e3 * self.kg, 14.593902937 * self.kg
# stress
self.pa = self.n / (self.m * self.m)
self.kpa, self.mpa, self.gpa = 1000 * self.pa, 1e6 * self.pa, 1e9 * self.pa
self.bar = 1e5 * self.pa
self.psi, self.ksi = 6894.7572932 * self.pa, 6894757.2932 * self.pa
self.psf, self.ksf = 47.880208 * self.pa, 47880.2468616010 * self.pa
def __getattr__(self, item):
v = re.findall(r'-?\d+\.?\d*e?E?-?\d*?', item)
if v:
v = float(v[0])
else:
return getattr(self, item.lower())
s = ''.join([x for x in item if x.isalpha()])
base = getattr(self, s)
return base ** v
def __repr__(self):
txt = "\n[bold #d20962]Length unit:[/bold #d20962]\n"
for i, unit in enumerate(unit_length):
txt += f"{unit}={getattr(self, unit)}; "
if i > 1 and (i + 1) % 5 == 0:
txt += "\n"
txt += "\n\n[bold #f47721]Force unit:[/bold #f47721]\n"
for i, unit in enumerate(unit_force):
txt += f"{unit}={getattr(self, unit)}; "
if i > 1 and (i + 1) % 5 == 0:
txt += "\n"
txt += "\n\n[bold #7ac143]Time unit:[/bold #7ac143]\n"
for i, unit in enumerate(unit_time):
txt += f"{unit}={getattr(self, unit)}; "
if i > 1 and (i + 1) % 5 == 0:
txt += "\n"
txt += "\n\n[bold #00bce4]Mass unit:[/bold #00bce4]\n"
for i, unit in enumerate(unit_mass):
txt += f"{unit}={getattr(self, unit)}; "
if i > 1 and (i + 1) % 5 == 0:
txt += "\n"
txt += "\n\n[bold #7d3f98]Pressure unit:[/bold #7d3f98]\n"
for i, unit in enumerate(unit_stress):
txt += f"{unit}={getattr(self, unit)}; "
if i > 1 and (i + 1) % 5 == 0:
txt += "\n"
rich.print(txt)
return ""
