numpy.matrix¶
-
class
numpy.matrix[source]¶ Returns a matrix from an array-like object, or from a string of data. A matrix is a specialized 2-D array that retains its 2-D nature through operations. It has certain special operators, such as
*(matrix multiplication) and**(matrix power).Parameters: data : array_like or string
If
datais a string, it is interpreted as a matrix with commas or spaces separating columns, and semicolons separating rows.dtype : data-type
Data-type of the output matrix.
copy : bool
See also
Examples
>>> a = np.matrix('1 2; 3 4') >>> print a [[1 2] [3 4]]
>>> np.matrix([[1, 2], [3, 4]]) matrix([[1, 2], [3, 4]])
Methods
all([axis, out])Test whether all matrix elements along a given axis evaluate to True. any([axis, out])Test whether any array element along a given axis evaluates to True. argmax([axis, out])Indices of the maximum values along an axis. argmin([axis, out])Return the indices of the minimum values along an axis. argpartition(kth[, axis, kind, order])Returns the indices that would partition this array. argsort([axis, kind, order])Returns the indices that would sort this array. astype(dtype[, order, casting, subok, copy])Copy of the array, cast to a specified type. byteswap(inplace)Swap the bytes of the array elements choose(choices[, out, mode])Use an index array to construct a new array from a set of choices. clip(a_min, a_max[, out])Return an array whose values are limited to [a_min, a_max].compress(condition[, axis, out])Return selected slices of this array along given axis. conj()Complex-conjugate all elements. conjugate()Return the complex conjugate, element-wise. copy([order])Return a copy of the array. cumprod([axis, dtype, out])Return the cumulative product of the elements along the given axis. cumsum([axis, dtype, out])Return the cumulative sum of the elements along the given axis. diagonal([offset, axis1, axis2])Return specified diagonals. dot(b[, out])Dot product of two arrays. dump(file)Dump a pickle of the array to the specified file. dumps()Returns the pickle of the array as a string. fill(value)Fill the array with a scalar value. flatten([order])Return a copy of the array collapsed into one dimension. getA()Return self as an ndarrayobject.getA1()Return self as a flattened ndarray.getH()Returns the (complex) conjugate transpose of self. getI()Returns the (multiplicative) inverse of invertible self. getT()Returns the transpose of the matrix. getfield(dtype[, offset])Returns a field of the given array as a certain type. item(*args)Copy an element of an array to a standard Python scalar and return it. itemset(*args)Insert scalar into an array (scalar is cast to array’s dtype, if possible) max([axis, out])Return the maximum value along an axis. mean([axis, dtype, out])Returns the average of the matrix elements along the given axis. min([axis, out])Return the minimum value along an axis. newbyteorder([new_order])Return the array with the same data viewed with a different byte order. nonzero()Return the indices of the elements that are non-zero. partition(kth[, axis, kind, order])Rearranges the elements in the array in such a way that value of the element in kth position is in the position it would be in a sorted array. prod([axis, dtype, out])Return the product of the array elements over the given axis. ptp([axis, out])Peak-to-peak (maximum - minimum) value along the given axis. put(indices, values[, mode])Set a.flat[n] = values[n]for all n in indices.ravel([order])Return a flattened array. repeat(repeats[, axis])Repeat elements of an array. reshape(shape[, order])Returns an array containing the same data with a new shape. resize(new_shape[, refcheck])Change shape and size of array in-place. round([decimals, out])Return a with each element rounded to the given number of decimals. searchsorted(v[, side, sorter])Find indices where elements of v should be inserted in a to maintain order. setfield(val, dtype[, offset])Put a value into a specified place in a field defined by a data-type. setflags([write, align, uic])Set array flags WRITEABLE, ALIGNED, and UPDATEIFCOPY, respectively. sort([axis, kind, order])Sort an array, in-place. squeeze([axis])Remove single-dimensional entries from the shape of a. std([axis, dtype, out, ddof])Return the standard deviation of the array elements along the given axis. sum([axis, dtype, out])Returns the sum of the matrix elements, along the given axis. swapaxes(axis1, axis2)Return a view of the array with axis1 and axis2 interchanged. take(indices[, axis, out, mode])Return an array formed from the elements of a at the given indices. tofile(fid[, sep, format])Write array to a file as text or binary (default). tolist()Return the matrix as a (possibly nested) list. tostring([order])Construct a Python string containing the raw data bytes in the array. trace([offset, axis1, axis2, dtype, out])Return the sum along diagonals of the array. transpose(*axes)Returns a view of the array with axes transposed. var([axis, dtype, out, ddof])Returns the variance of the matrix elements, along the given axis. view([dtype, type])New view of array with the same data.