1 | initial version |

While it's true that P1(float(0)) works, P1(-1) doesn't:

```
sage: P1(float(-1))
---------------------------------------------------------------------------
ValueError Traceback (most recent call last)
ValueError: negative number cannot be raised to a fractional power
```

I'm not sure what the best way to avoid this problem would be. Probably we could get away with coercing the function argument to RDF instead of float-- making that one change got the function to plot without difficulty. It's already done in lots of places in plot.py.

2 | No.2 Revision |

While it's true that P1(float(0)) works, ~~P1(-1) ~~P1(float(-1)) doesn't:

```
sage: P1(float(-1))
---------------------------------------------------------------------------
ValueError Traceback (most recent call last)
ValueError: negative number cannot be raised to a fractional power
```

I'm not sure what the best way to avoid this problem would be. Probably we could get away with coercing the function argument to RDF instead of float-- making that one change got the function to plot without difficulty. It's already done in lots of places in plot.py.

3 | No.3 Revision |

While it's true that P1(float(0)) works, P1(float(-1)) doesn't:

```
sage: P1(float(-1))
---------------------------------------------------------------------------
ValueError Traceback (most recent call last)
ValueError: negative number cannot be raised to a fractional power
```

I'm not sure what the best way to avoid this problem would be. Probably we could get away with coercing the function argument to RDF instead of ~~float-- ~~float before it's called-- making that one change got the function to plot without difficulty. It's already done in lots of places in plot.py.

4 | No.4 Revision |

While it's true that P1(float(0)) works, P1(float(-1)) doesn't:

```
sage: P1(float(-1))
---------------------------------------------------------------------------
ValueError Traceback (most recent call last)
ValueError: negative number cannot be raised to a fractional power
```

I'm not sure what the best way to avoid this problem would be. Probably we could get away with coercing the function argument to RDF instead of float before it's called-- making that one change in generate_plot_points got the function to plot without difficulty. It's already done in lots of places in ~~plot.py.~~plot.py, so maybe a few more wouldn't be a bad idea.

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