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Solve the tensor equation in Python

AmitDiwan
AmitDiwan
Updated on 25-Feb-2022 810 Views

To solve the tensor equation, use the numpy.linalg.tensorsolve() method in Python. It is assumed that all indices of x are summed over in the product, together with the rightmost indices of a, as is done in, for example, tensordot(a, x, axes=b.ndim).The 1st parameter, a is a coefficient tensor, of shape b.shape + Q. Q, a tuple, equals the shape of that sub-tensor of a consisting of the appropriate number of its rightmost indices, and must be such that prod(Q) == prod(b.shape). The 2nd parameter, b is a right-hand tensor, which can be of any shape. The 3rd parameter, axis is ...

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Replace infinity with large finite numbers but fill NaN values in Python

AmitDiwan
AmitDiwan
Updated on 25-Feb-2022 1K+ Views

To replace NaN with zero and infinity with large finite numbers, use the numpy.nan_to_num() method in Python. The method returns, x, with the non-finite values replaced. If copy is False, this may be x itself. The 1st parameter is the input data. The 2nd parameter is copy, whether to create a copy of x (True) or to replace values in-place (False). The in-place operation only occurs if casting to an array does not require a copy. Default is True.The 3rd parameter is nan, the value to be used to fill NaN values. If no value is passed then NaN values ...

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Replace NaN with zero and infinity with large finite numbers in Python

AmitDiwan
AmitDiwan
Updated on 25-Feb-2022 425 Views

To replace NaN with zero and infinity with large finite numbers, use the numpy.nan_to_num() method in Python. The method returns, x, with the non-finite values replaced. If copy is False, this may be x itself. The 1st parameter is the input data. The 2nd parameter is copy, whether to create a copy of x (True) or to replace values in-place (False). The in-place operation only occurs if casting to an array does not require a copy. Default is True.The 3rd parameter is nan, the value to be used to fill NaN values. If no value is passed then NaN values ...

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Return the square of the complex-value input in Python

AmitDiwan
AmitDiwan
Updated on 25-Feb-2022 236 Views

To return the element-wise square of the array input, use the numpy.square() method in Python. The method returns the element-wise x*x, of the same shape and dtype as x. This is a scalar if x is a scalar. The 1st parameter, x is the input data. The 2nd parameter, out is a location into which the result is stored. If provided, it must have a shape that the inputs broadcast to. If not provided or None, a freshly-allocated array is returned. A tuple (possible only as a keyword argument) must have length equal to the number of outputs.The 3rd parameter, ...

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Return the lowest index in the string where substring is found in a range using Python index()

AmitDiwan
AmitDiwan
Updated on 25-Feb-2022 178 Views

Return the lowest index in the string where substring sub is found using the numpy.char.index() method in Python Numpy. The method returns the output array of ints. Raises ValueError if sub is not found. The first parameter is the input array. The second parameter is the substring to be searched. The third and fourth parameter are optional arguments, wherein start and end are interpreted as in slice notation.StepsAt first, import the required library −import numpy as npCreate a One-Dimensional array of strings −arr = np.array(['KATIE', 'KATE', 'CRATE']) Displaying our array −print("Array...", arr)Get the datatype −print("Array datatype...", arr.dtype) Get the dimensions ...

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Return the lowest index in the string where substring is found using Python index()

AmitDiwan
AmitDiwan
Updated on 25-Feb-2022 328 Views

Return the lowest index in the string where substring sub is found using the numpy.char.index() method in Python Numpy. The method returns the output array of ints. Raises ValueError if sub is not found. The first parameter is the input array. The second parameter is the substring to be searched.StepsAt first, import the required library −import numpy as npCreate a One-Dimensional array of strings −arr = np.array(['KATIE', 'KATE']) Displaying our array −print("Array...", arr)Get the datatype −print("Array datatype...", arr.dtype) Get the dimensions of the Array −print("Array Dimensions...", arr.ndim)Get the shape of the Array −print("Our Array Shape...", arr.shape) Get the number of ...

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Compute log-determinants for a stack of matrices in Python

AmitDiwan
AmitDiwan
Updated on 25-Feb-2022 269 Views

To compute log-determinants for a stack of matrices, use the numpy.linalg.slogdet() method in Python. The 1st parameter, s is an input array, has to be a square 2-D array. The method, with sign returns a number representing the sign of the determinant. For a real matrix, this is 1, 0, or -1. For a complex matrix, this is a complex number with absolute value 1, or else 0.The method, with logdet returns the natural log of the absolute value of the determinant. If the determinant is zero, then sign will be 0 and logdet will be -Inf. In all cases, ...

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Return matrix rank of array using Singular Value Decomposition method in Python

AmitDiwan
AmitDiwan
Updated on 25-Feb-2022 681 Views

To return matrix rank of array using Singular Value Decomposition method, use the numpy.linalg.matrix_rank() method in Python. Rank of the array is the number of singular values of the array that are greater than tol. The 1st parameter, A is the input vector or stack of matrices.The 2nd parameter, tol is the Threshold below which SVD values are considered zero. If tol is None, and S is an array with singular values for M, and eps is the epsilon value for datatype of S, then tol is set to S.max() * max(M, N) * eps. The 3rd parameter, hermitian, If ...

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Compute element-wise arc tangent of x1/x2 choosing the quadrant correctly in Python

AmitDiwan
AmitDiwan
Updated on 25-Feb-2022 204 Views

The quadrant is chosen so that arctan2(x1, x2) is the signed angle in radians between the ray ending at the origin and passing through the point (1, 0), and the ray ending at the origin and passing through the point (x2, x1).The 1st parameter is the y-coordinates. The 2nd parameter is the x-coordinates. If x1.shape != x2.shape, they must be broadcastable to a common shape. The method returns array of angles in radians, in the range [-pi, pi]. This is a scalar if both x1 and x2 are scalars.StepsAt first, import the required library −import numpy as npCreating arrays using ...

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Get the Trigonometric inverse cosine in Python

AmitDiwan
AmitDiwan
Updated on 25-Feb-2022 5K+ Views

The arccos is a multivalued function: for each x there are infinitely many numbers z such that cos(z) = x. The convention is to return the angle z whose real part lies in [0, pi]. For real-valued input data types, arccos always returns real output. For each value that cannot be expressed as a real number or infinity, it yields nan and sets the invalid floating point error flag. For complex-valued input, arccos is a complex analytic function that has branch cuts [-inf, -1] and [1, inf] and is continuous from above on the former and from below on the ...

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