If you want to plot this as a function, you'll need to write out theQuote:> here is my function to be graphed:
> F(X) = (X^t * A * X)^2 // X^t denotes the transpose of X
> // ^2 denotes raise to the 2nd power
> X is a vector, A is a symmetric square matrix.
> For 2x2 A and X =(x, y) F(X) is a surface in 3-D.
> The x-axis has the x component of X and the y-axis the y
> component of X. The z-axis has the value F(X) which is a scalar.
> How can I graph something like that? What sort of entries the data
> file needs? I tried different things but nothing seems to work right!
equation in scalar form as F(x,y) = ... because gnuplot doesn't have
vector arithmatic built-in.
Of course, you could always define your own 2x2 vector functions for
If you want to prepare a data file, it should be in "grid" format, which
looks like this:
x00 y00 z00
x10 y10 z10
x20 y20 z20
. . .
xN0 yN0 zN0
[null line -- nothing except newline and/or return]
x01 y01 z01
x11 y11 z11
x21 y21 z21
. . .
xN1 yN1 zN1
x02 y02 z02
x12 y12 z12
x22 y22 z22
. . .
xN2 yN2 zN2
and so on.