Exemple #1
0
    def fit(self, X, y):
        self._check(X, y)
        if dim(y) == 1:
            raw_X = X
            if self.fit_intercept:
                X = hstack([ones(shape(X)[0], 1), X])

            beta = zeros(shape(X)[1])  # row vector
            X_T = matrix_transpose(X)

            if self.fit_intercept:
                beta[0] = sum(minus(reshape(y, -1), dot(
                    raw_X, beta[1:]))) / (shape(X)[0])

            for _ in range(self.max_iter):
                start = 1 if self.fit_intercept else 0
                for j in range(start, len(beta)):
                    tmp_beta = [x for x in beta]
                    tmp_beta[j] = 0.0

                    r_j = minus(reshape(y, -1), dot(X, beta))
                    # r_j = minus(reshape(y,-1) , dot(X, tmp_beta))
                    arg1 = dot(X_T[j], r_j)
                    arg2 = self.alpha * shape(X)[0]

                    if sum(square(X_T[j])) != 0:
                        beta[j] = self._soft_thresholding_operator(
                            arg1, arg2) / sum(square(X_T[j]))
                    else:
                        beta[j] = 0

                    if self.fit_intercept:
                        beta[0] = sum(
                            minus(reshape(y, -1), dot(
                                raw_X, beta[1:]))) / (shape(X)[0])
                # # add whatch
                # self.beta = beta
                # self._whatch(raw_X,y)

            if self.fit_intercept:
                self.intercept_ = beta[0]
                self.coef_ = beta[1:]
            else:
                self.coef_ = beta
            self.beta = beta
            return self
        elif dim(y) == 2:
            if self.fit_intercept:
                X = hstack([ones(shape(X)[0], 1), X])
            y_t = matrix_transpose(y)
            betas = []
            for i in range(shape(y)[1]):
                betas.append(self._fit(X, y_t[i]))
            batas = matrix_transpose(betas)
            self.betas = batas
    def fit(self, X, y, weights=None):
        X, y = self._check(X, y)

        if self.fit_intercept:
            m, n = shape(X)
            bias = ones(m, 1)
            X = hstack([bias, X])

        eye = identity_matrix(shape(X)[1])
        from linalg.matrix import diag
        if not self.penalty_bias:
            eye[0][0] = 0

        # add weights
        if weights != None:
            assert (len(weights) == shape(X)[0])
            X = matrix_matmul(diag(weights), X)

        X_T = matrix_transpose(X)

        self.W = matrix_matmul(
            matrix_matmul(
                matrix_inverse(
                    plus(matrix_matmul(X_T, X),
                         multiply(eye,
                                  self.alpha * shape(X)[0]))
                    # plus(matrix_matmul(X_T,X),multiply(eye,self.alpha))
                ),
                X_T),
            y)
        self.importance_ = sum(self.W, axis=1)
        if self.fit_intercept:
            self.importance_ = self.importance_[1:]
Exemple #3
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 def predict(self, X):
     assert (self.beta != None or self.betas != None)
     if self.fit_intercept:
         X = hstack([ones(shape(X)[0], 1), X])
     if self.beta != None:
         return dot(X, self.beta)
     else:
         return matrix_matmul(X, self.betas)
 def predict(self, X):
     assert (self.W != None)
     if self.fit_intercept:
         m, n = shape(X)
         bias = ones(m, 1)
         X = hstack([bias, X])
     result = matrix_matmul(X, self.W)
     if self.dim_Y == 1:
         result = [x[0] for x in result]
     return result
Exemple #5
0
    def fit(self, X, y):
        X, y = self._check(X, y)
        if self.fit_intercept:
            m, n = shape(X)
            bias = ones(m, 1)
            X = hstack([bias, X])

        X_T = matrix_transpose(X)
        # print matrix_matmul(X_T,X)
        self.W = matrix_matmul(
            matrix_matmul(matrix_inverse(matrix_matmul(X_T, X)), X_T), y)
    def fit(self, X, y):
        X, y = self._check(X, y)

        if self.fit_intercept:
            m, n = shape(X)
            bias = ones(m, 1)
            X = hstack([bias, X])

        eye = identity_matrix(shape(X)[1])
        from linalg.matrix import diag
        if self.penalty_loss:
            eye = diag(self.penalty_loss)
        X_T = matrix_transpose(X)

        self.W = matrix_matmul(
            matrix_matmul(
                matrix_inverse(
                    plus(matrix_matmul(X_T, X),
                         multiply(eye,
                                  self.alpha * shape(X)[0]))), X_T), y)
        self.importance_ = sum(self.W, axis=1)
        if self.fit_intercept:
            self.importance_ = self.importance_[1:]