Need of Tangle calculation using code and Numerically

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To calculate the tangle, the square concurrence values of the ABC states are essential, as defined in the tangle equation T=1/4 (C_A^2 + C_B^2 + C_C^2 - 2C_AC_B - 2C_BC_C - 2C_AC_C). The calculation of these concurrences requires using the partial trace formula, specifically C_AB = Tr[sqrt(ρAB*σAB*ρAB*σAB)] - Tr[ρAB²], where ρAB is the density matrix of the composite system and σAB is the swap operator. This process must be repeated for subsystems B and C to derive their respective concurrences. Once all concurrences are determined, they can be substituted into the tangle equation to compute the tangle value. Accurate calculations of these components are crucial for obtaining the correct tangle.
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Homework Statement
How to find the tangle for the 3 qubit state in GHZ class and W class? (Using code in MATLAB and also numerically)
Relevant Equations
Tangle equation
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= tangle equation
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= Inequality condition
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= partial trace formula.

To find the tangle, we need the square concurrence value of ABC states as mentioned in a tangle equation. I am not able to find the value of square concurrence.
 
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The tangle equation is given by:T=1/4 (C_A^2 + C_B^2 + C_C^2 - 2C_AC_B - 2C_BC_C - 2C_AC_C),where C_A, C_B and C_C are the concurrences between subsystems A, B and C respectively.To solve for the tangle, we need to first calculate the concurrence of each subsystem. This can be done using the partial trace formula, which is given by:C_AB = Tr[sqrt(ρAB*σAB*ρAB*σAB)] - Tr[ρAB²],where ρAB is the density matrix of the composite system AB and σAB is the swap operator. Similarly, the concurrences for subsystems B and C can be calculated using the same formula with appropriate substitutions. Once the concurrences for all three subsystems have been calculated, we can then plug them into the tangle equation to obtain the tangle.
 
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