Re: [Tutor] Problems with subtraction!

2010-07-07 Thread col speed
On 7 July 2010 18:59, Evert Rol wrote: > > The second number should be negative ( I WANT it to be negative). For > example: > > > > print (0 - t[4])*(t[3] - t[5]) , (0 - t[5])*(t[2] - t[4]) gives : > > > > -30895 -935636 > > > > And in the python shell: > > > > >>> -30895 -935636 > > -966531 >

Re: [Tutor] Problems with subtraction!

2010-07-07 Thread Evert Rol
> The second number should be negative ( I WANT it to be negative). For example: > > print (0 - t[4])*(t[3] - t[5]) , (0 - t[5])*(t[2] - t[4]) gives : > > -30895 -935636 > > And in the python shell: > > >>> -30895 -935636 > -966531 No, because you have to *subtract* the second answer from

[Tutor] Problems with subtraction!

2010-07-07 Thread col speed
I apologise in advance for such a silly question. Normally, I start to write to the list and work the answer out before sending the mail. Not this time. I'm trying to work out which triangles contain the cartesian origin (0, 0) and have the following: t = [-340, 495, -153, -910, 835, -947] print