chebyshev example

src/pke/examples/function-evaluation.py

@@ -0,0 +1,94 @@
+from openfhe import *
+import math
+
+def main():
+    EvalLogisticExample()
+    EvalFunctionExample()
+
+def EvalLogisticExample():
+    print("--------------------------------- EVAL LOGISTIC FUNCTION ---------------------------------\n")
+    parameters = CCParamsCKKSRNS()
+    parameters.SetSecurityLevel(SecurityLevel.HEStd_NotSet)
+    parameters.SetRingDim(1 << 10)
+
+    scalingModSize = 59
+    firstModSize = 60
+
+    parameters.SetScalingModSize(scalingModSize)
+    parameters.SetFirstModSize(firstModSize)
+
+    polyDegree = 16
+    multDepth = 6
+
+    parameters.SetMultiplicativeDepth(multDepth)
+    cc = GenCryptoContext(parameters)
+    cc.Enable(PKESchemeFeature.PKE)
+    cc.Enable(PKESchemeFeature.KEYSWITCH)
+    cc.Enable(PKESchemeFeature.LEVELEDSHE)
+    cc.Enable(PKESchemeFeature.ADVANCEDSHE)
+
+    keyPair = cc.KeyGen()
+    cc.EvalMultKeyGen(keyPair.secretKey)
+
+    input = [-4, -3, -2, -1, 0, 1, 2, 3, 4]
+    encodedLength = len(input)
+    plaintext = cc.MakeCKKSPackedPlaintext(input)
+    ciphertext = cc.Encrypt(keyPair.publicKey, plaintext)
+
+    lowerBound = -4
+    upperBound = 4
+    result = cc.EvalLogistic(ciphertext, lowerBound, upperBound, polyDegree)
+
+    plaitextDec = Decrypt(result, keyPair.secretKey)
+    plaitextDec.SetLength(encodedLength)
+
+    expectedOutput = [0.0179885, 0.0474289, 0.119205, 0.268936, 0.5, 0.731064, 0.880795, 0.952571, 0.982011]
+    print(f"Expected output\n\t {expectedOutput}\n")
+
+    finalResult = plaitextDec.GetCKKSPackedValue()
+    print(f"Actual output\n\t {finalResult}\n")
+
+def EvalFunctionExample():
+    print("--------------------------------- EVAL SQUARE ROOT FUNCTION ---------------------------------\n")
+    parameters = CCParamsCKKSRNS()
+    parameters.SetSecurityLevel(SecurityLevel.HEStd_NotSet)
+    parameters.SetRingDim(1 << 10)
+
+    scalingModSize = 59
+    firstModSize = 60
+
+    parameters.SetScalingModSize(scalingModSize)
+    parameters.SetFirstModSize(firstModSize)
+
+    polyDegree = 50
+    multDepth = 7
+
+    parameters.SetMultiplicativeDepth(multDepth)
+    cc = GenCryptoContext(parameters)
+    cc.Enable(PKESchemeFeature.PKE)
+    cc.Enable(PKESchemeFeature.KEYSWITCH)
+    cc.Enable(PKESchemeFeature.LEVELEDSHE)
+    cc.Enable(PKESchemeFeature.ADVANCEDSHE)
+
+    keyPair = cc.KeyGen()
+    cc.EvalMultKeyGen(keyPair.secretKey)
+
+    input = [1, 2, 3, 4, 5, 6, 7, 8, 9]
+    encodedLength = len(input)
+    plaintext = cc.MakeCKKSPackedPlaintext(input)
+    ciphertext = cc.Encrypt(keyPair.publicKey, plaintext)
+
+    lowerBound = 1
+    upperBound = 9
+    result = cc.EvalChebyshevFunction(math.sqrt,ciphertext, lowerBound, upperBound, polyDegree)
+
+    plaintextDec = Decrypt(result, keyPair.secretKey)
+    plaintextDec.SetLength(encodedLength)
+
+    expectedOutput = [1, 1.414213, 1.732050, 2, 2.236067, 2.449489, 2.645751, 2.828427, 3]
+    print(f"Expected output\n\t {expectedOutput}\n")
+
+    finalResult = plaintextDec.GetCKKSPackedValue()
+    print(f"Actual output\n\t {finalResult}\n")
+if __name__ == "__main__":
+    main()