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Some methods for symbolic expressions have a hold argument, that allows to prevent simplification of expressions. For example:

sage: a = sqrt(2)
sage: a.parent()
Symbolic Ring
sage: a^2
2
sage: a.power(2)
2
sage: a.power(2,hold=True)
sqrt(2)^2

It also works for addition in certain cases:

sage: x.parent()
Symbolic Ring
sage: x.add(x, hold=True) 
x + x

Unfortunately, it seems not to work for elements of the Symbolic Ring that represent integers:

sage: a = SR(2)
sage: a.parent()
Symbolic Ring
sage: a
2
sage: a.add(SR(3),hold=True)
5

Some methods for symbolic expressions have a hold argument, that allows to prevent simplification of expressions. For example:

sage: a = sqrt(2)
sage: a.parent()
Symbolic Ring
sage: a^2
2
sage: a.power(2)
2
sage: a.power(2,hold=True)
a.power(2, hold=True)
sqrt(2)^2

It also works for addition in certain cases:

sage: x.parent()
Symbolic Ring
sage: x.add(x, hold=True) 
x + x

Unfortunately, it seems not to work for elements of the Symbolic Ring that represent integers:

sage: a = SR(2)
sage: a.parent()
Symbolic Ring
sage: a
2
sage: a.add(SR(3),hold=True)
a.add(SR(3), hold=True)
5

Some methods for symbolic expressions have a hold argument, that this allows to prevent simplification of expressions. For example:

sage: a = sqrt(2)
sage: a.parent()
Symbolic Ring
sage: a^2
2
sage: a.power(2)
2
sage: a.power(2, hold=True)
sqrt(2)^2

It also works for addition in certain cases:

sage: x.parent()
Symbolic Ring
sage: x.add(x, hold=True) 
x + x

Unfortunately, it seems not to work for elements of the Symbolic Ring that represent integers:

sage: a = SR(2)
sage: a.parent()
Symbolic Ring
sage: a
2
sage: a.add(SR(3), hold=True)
5

Some methods for symbolic expressions have a hold argument, this allows to prevent simplification of expressions. For example:

sage: a = sqrt(2)
sage: a.parent()
Symbolic Ring
sage: a^2
2
sage: a.power(2)
2
sage: a.power(2, hold=True)
sqrt(2)^2
sage: pi.cos(hold=True)
cos(pi)

It also works for addition in certain cases:

sage: x.parent()
Symbolic Ring
sage: x.add(x, hold=True) 
x + x

Unfortunately, it seems not to work for elements of the Symbolic Ring that represent integers:

sage: a = SR(2)
sage: a.parent()
Symbolic Ring
sage: a
2
sage: a.add(SR(3), hold=True)
5