PythonObject <<= Thing -- augmented left shift for Python objects

Operator: <<=
Usage:

x <<= y
Inputs:
- x, a python object,
- y, a thing,
Outputs:
- a python object, x shifted left by y, assigned to x;

Description

Perform the left shift operator on Python objects, and assign the result to the first argument.

i1 : x = toPython 1

o1 = 1

o1 : PythonObject of class int

i2 : x <<= toPython 3

o2 = 8

o2 : PythonObject of class int

i3 : x

o3 = 8

o3 : PythonObject of class int

If the right-hand side is a Macaulay2 object, then it is first converted to a Python object before shifting.

i4 : x = toPython 1

o4 = 1

o4 : PythonObject of class int

i5 : x <<= 5

o5 = 32

o5 : PythonObject of class int

i6 : x

o6 = 32

o6 : PythonObject of class int

If the Python class of x defines an __ilshift__ method for in-place left shift, then it will be called. Otherwise, x will be shifted by y in the usual way, creating a new Python object that is assigned back to x.

For example, NumPy arrays support in-place left shift. In the example below, x is modified directly, and no new object is created.

i7 : installNumPyMethods();

i8 : x = toPython matrix {{1, 2}, {4, 8}}

o8 =  [[1 2]
       [4 8]]

o8 : PythonObject of class numpy.ndarray

i9 : x <<= 2

o9 = [[ 4  8]
      [16 32]]

o9 : PythonObject of class numpy.ndarray

i10 : x

o10 = [[ 4  8]
       [16 32]]

o10 : PythonObject of class numpy.ndarray

Ways to use this method:

PythonObject <<= Thing -- augmented left shift for Python objects

The source of this document is in Python/doc/bitwise.m2:100:0.

PythonObject <<= Thing -- augmented left shift for Python objects

Description

See also

Ways to use this method: