TypeError: float() argument must be a string or a number, not 'list'

TypeError: float() argument must be a string or a number, not 'list' - Printable Version

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TypeError: float() argument must be a string or a number, not 'list' - Anldra12 - Jul-01-2022

I am working on project Shamir secret sharing scheme get the error

ef generateK(pShares, x_subi, Subset, q):
    y_subset = []
    x_subset = []

    Subset.sort()
    for ID in Subset:
        y_i = pShares[ID]
        x_i = x_subi[ID]
        y_subset.append(y_i)
        x_subset.append(x_i)

    recoveredK = 0
    for j in range(1, (len(x_subset))):
        x_j = x_subset[j]
        b_j = 1
        for L in range(1, len(x_subset)):
            if (L != j):
                x_L = x_subset[L]
                newCoeff = float(x_L)/(x_L - x_j) 
                b_j = b_j * newCoeff
        recoveredK += y_subset[j] * (b_j)

    recoveredK_int = int(round(recoveredK))
    print(" The secret value recovered k：", recoveredK_int)

    return recoveredK_int

Error:Enter list of Participant i secrets
10 1 3 16
Traceback (most recent call last):
  File "/home/ali/Downloads/Attribute-Based-Encryption-master/LSSS_t,n.py", line 276, in <module>
    runPackage([], [])
  File "/home/ali/Downloads/Attribute-Based-Encryption-master/LSSS_t,n.py", line 260, in runPackage
    predefinedVars, returnK = initiateScheme(predefinedVars)
  File "/home/ali/Downloads/Attribute-Based-Encryption-master/LSSS_t,n.py", line 57, in initiateScheme
    recovered_k = runScheme(t, n, secret_k, q, Field)
  File "/home/ali/Downloads/Attribute-Based-Encryption-master/LSSS_t,n.py", line 144, in runScheme
    generatedK = tryAccessStructure(k, pShares, x_subi, t_str, q)
  File "/home/ali/Downloads/Attribute-Based-Encryption-master/LSSS_t,n.py", line 169, in tryAccessStructure
    generatedK = generateK(pShares, x_subi, P_Subset, q)
  File "/home/ali/Downloads/Attribute-Based-Encryption-master/LSSS_t,n.py", line 249, in generateK
    newCoeff = float(x_L)/(x_L - x_j)
TypeError: float() argument must be a string or a number, not 'list

RE: TypeError: float() argument must be a string or a number, not 'list' - BashBedlam - Jul-01-2022

If you plug-in these values and call your function

generateK ([1, 2, 3], [1, 2, 3], [1, 2], 1)

then it works as expected like so.

Output:
 The secret value recovered k： 3

It would seem that the problem is somewhere else in you code.

RE: TypeError: float() argument must be a string or a number, not 'list' - deanhystad - Jul-01-2022

To debug I would set a breakpoint and look at the arguments. If you don't have debugging you can use print.

print(x_L, x_j)
                newCoeff = float(x_L)/(x_L - x_j)

One of these will be a list. Knowing which will direct where you put the next print statement.