1 | initial version |

It seems that this version does not ignore the x*y case:

```
p=contour_plot(lambda x,y: F(x,y), (x,0,1), (y,0,1) )
p.show()
```

2 | No.2 Revision |

It seems that this version does not ignore the x*y case:

```
p=contour_plot(lambda x,y: F(x,y), (x,0,1), (y,0,1) )
p.show()
```

Lambda is not necessary:

```
def F(x,y):
if( x <= y ):
return x*y
return x+y
contour_plot( F, (x,0,1), (y,0,1) ).show()
```

Copyright Sage, 2010. Some rights reserved under creative commons license. Content on this site is licensed under a Creative Commons Attribution Share Alike 3.0 license.