# crash: intersect(line, ellipse)

Tang Dashi shared this problem 1 year ago
New

Intersect(a,b) command with two parameter curves (line and ellipse), the app crushed.

intersect(a,b)  1

read the help. the syntax for curve needs initial values for parameters or try implicit form or better conic and line

ie: conic(a(0),a(1),a(2),a(3),a(4)); line(b(1),b(3)) 1

read the help. the syntax for curve needs initial values for parameters. try implicit form or better conic and line

ie: conic(a(0),a(1),a(2),a(3),a(4)); line(b(1),b(3))

the ¿bug? needs a check your input message 1

If you input

intersect(a,b,-3,3)

the CPU 100%, and no result.

maybe not a bug. but it really has something. 1

in that file, there is another bug: 1

in that file, there is another bug:

when you input:

(2cos(θ), 4sin(θ))

it is ok. but when you save and re-open, it is "undefined"

win10+Geogebra5.0.579-d 1

newly i think (2cos(θ), 4sin(θ)) that returns X=(0,0)+(2cos(θ), 4sin(θ)) is not supported syntax

the correct syntax for parametric curves is curve(2cos(θ), 4sin(θ),θ,0,2 pi)

I think there is a bad interpretation with X=(1,2)+t (3,4) for lines and (2cos(θ);θ) for polar curves 1

newly i think (2cos(θ), 4sin(θ)) that returns X=(0,0)+(2cos(θ), 4sin(θ)) is not supported syntax

the correct syntax for parametric curves is curve(2cos(θ), 4sin(θ),θ,0,2 pi)

it is possible Curve((2cos(θ), 4sin(θ)), θ, 0, 2π) also

I think there is a bad interpretation with X=(1,2)+t (3,4) for lines and (2cos(θ);θ) for polar curves 1

thank you, mathmagic!

I knew that reason, I think that the application should has strict syntext，that will minimize ambiguity.