Is there a function that lets you know if a given expression is a polynomial?

The `polynomial_coeffs`

function can be used for this.

1 Like

This seems to work:

```
function isSingleVariablePoly(espr)
variables = Symbolics.get_variables(espr)
if !isone(length(variables))
return false
end
x = variables[1]
Symbolics._iszero(Symbolics.polynomial_coeffs(espr, [x])[2]) ? true : false
end
```

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That should work. It might be more flexible to allow the user to pass the variables in, such as:

```
function is_poly(expr, vars)
p,r = polynomial_coeffs(expr, vars)
length(intersect(Symbolics.get_variables(r), vars)) == 0
end
```

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