[Python] TypeError: '>' not supported between instances of 'list' and 'float'

def Diffu(c, T):
c = np.array(c)
print(f"Type of c: {type(c)}, Value: {c}")
return D_coe[W, 0] * np.exp(D_coe[W, 1] * (FSP * (c > FSP) + c * (c <= FSP)) - D_coe[W, 2] / T)


Below is the whole code block that includes def Diffu(c,T)

def getMC(W, Th, c, Nt, T, RH):
# Constants in the diffusion coefficient formula, arranged in rows by wood type.
D_coe = np.array([[5.69e-4, 1.06, 5190],
[12e-4, 0.01, 5290],
[15e-4, 0.6, 5380]])

# Model parameters
L = Th * 0.0254 / 2 # Length of the symmetric computational domain (m)
nx = 200 # Number of spatial steps
dx = L / (nx - 1) # Spatial step size
dt = 0.005 * 3600 # Time step (s)
nt = Nt * (3600 / dt) # Number of time steps
alpha = dt / dx**2 # Precompute constants
e = np.zeros((nx, nx)) # Create coefficient matrix for the implicit scheme

# Convert temperature from degF to K
def FtoK(F):
return (F - 32) * 5 / 9 + 273.15

T = FtoK(T)

# Define the function for the equilibrium moisture content, EMC(RH, T)
k1 = -0.000612
k2 = 2.43
k3 = 0.0577
k4 = 0.430
Tc = 647.1

def EMC(RH, T):
return (k1 * T * (1 - T / Tc) ** k2 * np.log(1 - RH)) ** (k3 * T ** k4)

# Define the function for the diffusion coefficient, D(c, T)
FSP = 0.3 # The fiber saturation point, 30%

def Diffu(c, T):
c = np.array(c)
print(f"Type of c: {type(c)}, Value: {c}")
return D_coe[W, 0] * np.exp(D_coe[W, 1] * (FSP * (c > FSP) + c * (c <= FSP)) - D_coe[W, 2] / T)

# Numerical scheme (2nd-order in time, and 4th-order in space)
for n in range(int(nt)):
# Set the surface moisture content to the equilibrium moisture content
c[0] = EMC(RH, T)

# Calculate diffusion coefficients for the current time step
D = Diffu(c, T)

# Assemble coefficient matrix for the implicit scheme
# 4th-order central difference
for i in range(2, nx - 2):
A = np.array([[1, -8, -12, 8, -1],
[-8, 64, 192, -64, 8],
[0, 0, -360, 0, 0],
[8, -64, 192, 64, -8],
[-1, 8, -12, -8, 1]])
e[i, i - 2:i + 2] = D[i - 2:i + 2] @ A.T

# 4th-order scheme at the boundaries
B = np.array([[9, 162, -54, 18, -3],
[30, -140, -180, 60, -10],
[-54, -108, 324, -108, 18],
[18, 108, -108, 36, -6],
[-3, -22, 18, -6, 1]])
e[1, 0:5] = D[0:5] @ B.T
e[-2, -1:-6:-1] = D[-1:-6:-1] @ B.T

# Crank–Nicolson method
E1 = 2 * np.eye(nx) - alpha * e / 144
E2 = 2 * np.eye(nx) + alpha * e / 144

# Dirichlet boundary condition at the surface
E1[0, 0] = 1
E2[0, 0] = 1

# Neumann boundary condition at the symmetry axis, 4th-order
E1[nx - 1, nx - 5:nx] = np.array([3, -16, 36, -48, 25]) / 12 * dt / dx
E2[-1, -1] = 0

# Solve for the moisture content distribution
b = c.copy()
c = np.linalg.solve(E1, E2 @ b)

MC = c

# Compute the average moisture content over the domain
MC_avg = (np.sum(c) + np.sum(c[1:-1])) / 2 / (nx - 1)

return MC, MC_avg


When I run my main code that calls the functions in this code, I get the following error:

File ~\Desktop\DK\3.WDHP\HPWoodSim\functions.py:246, in getMC(W, Th, c, Nt, T, RH)
242 for n in range(int(nt)):
243 # Set the surface moisture content to the equilibrium moisture content
244 c[0] = EMC(RH, T)
--> 246 # Calculate diffusion coefficients for the current time step
247 D = Diffu(c, T)
249 # Assemble coefficient matrix for the implicit scheme
250 # 4th-order central difference

File ~\Desktop\DK\3.WDHP\HPWoodSim\functions.py:238, in Diffu(c, T)
235 # Define the function for the diffusion coefficient, D(c, T)
236 FSP = 0.3 # The fiber saturation point, 30%
--> 238 def Diffu(c, T):
239 return D_coe[W, 0] * np.exp(D_coe[W, 1] * (FSP * (c > FSP) + c * (c <= FSP)) - D_coe[W, 2] / T)
241 # Numerical scheme (2nd-order in time, and 4th-order in space)

TypeError: '>' not supported between instances of 'list' and 'float'


I tried entering c = np.array(c) to make it into an array, but it doesn't seem to solve the issue.

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