def load_convs(filename):
"""Read conversion factors from the given file.
The file format is line-based:
from [whitespace] to [whitespace] factor
Anything past the third element is ignored. Lines starting with # are
ignored.
"""
convs = []
with open(filename, "r") as f:
for line in f:
parts = line.split()
if line.startswith("#") or len(parts) < 3:
continue
convs.extend(factor_conv(tokens.parse_infix(parts[0]), tokens.parse_infix(parts[1]), parts[2]))
return convs
path, _to = find_conversion_path(convs, frm, to)
value = frm.value
for conv in path:
value = conv.func(value)
ret = _to.copy()
ret.value = value
return ret
def simplify(convs, frm):
return convert(convs, frm, None)
if __name__ == "__main__":
print "pynuts conversion demo"
convs = load_convs("data.txt")
# print convert(convs, tokens.parse_infix('2 W h'), tokens.parse_infix('J'))
print "Simplify 2 mol/L * N_A:"
jph = tokens.parse_infix("2 mol/L * N_A")
target = simplify(convs, jph)
print convert(convs, jph, target)
print "Convert 3 ha to km^2"
print convert(convs, tokens.parse_infix("3 ha"), tokens.parse_infix("km^2"))
print "Convert 5 furlongs per fortnight to meter per hour"
print convert(convs, tokens.parse_infix("5 fur/ftn"), tokens.parse_infix("m/h"))