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mph- / lcapy

Lcapy is a Python package for symbolic linear circuit analysis and signal processing. It uses SymPy for symbolic mathematics.
GNU Lesser General Public License v2.1
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double units and wrong units combinations #139

Open TheHowland opened 1 week ago

TheHowland commented 1 week ago

When accessing the the current and voltage of the component the matamatically interpreted result is V*2 for voltage and P for current. The Current has VA in the expressoin which physically would represent power instead of ampere. I suspect that it is because the expression has a symbol named 'V' which seems to not be the Voltage Symbol 'V'. Accessing the units property yields the correct unit.

from lcapy import t
from lcapy import state

state.show_units = True

cct = Circuit('''V1 0 1 dc {10}; up
W 1 2; right
R1 2 3 {1000}; down
W 3 0; left
''')
voltage = cct.R1.V(t)
current = cct.R1.I(t)

print("Voltage: " + str(voltage))
print("Current: " + str(current))`

output: Voltage: V(-10V) Current: A(-V/100) for V1 0 1 ac {10} {0} {100}; up Voltage: V(-10Vcos(100t)) Current: A(-Vcos(100t)/100)

mph- commented 6 days ago

Thanks for letting me know. Yes there is a bug when show_units is enabled. I've tracked down the source of the problem and will ponder a fix tomorrow.