Why doesn't this RegionPlot3D not plot anything?
RegionPlot3D[ 0 < Subscript[y, 1] < 1 && Subscript[y, 2] == 0 && Subscript[y, 3] == 1 - Subscript[y, 1] && Subscript[x, 1] == 1 && Subscript[x, 2] == 0 && Subscript[x, 3] == 0, {Subscript[y, 1], 0, 1}, {Subscript[y, 2], 0, 1}, {Subscript[y, 3], 0, 1}]
The result I would expect would be this one:
RegionPlot3D[ 0 < Subscript[y, 1] < 1 && Subscript[y, 2] == 0 && Subscript[y, 3] == 1 - Subscript[y, 1], {Subscript[y, 1], 0, 1}, {Subscript[y, 2], 0, 1}, {Subscript[y, 3], 0, 1}]
I have much more complicated expressions than this, where the common theme is that there will be 3 free variables which I specify where to plot (here, $y_1, y_2, y_3$) and all other variables will be given, like above (e.g., $x_1, x_2, x_3$ here) and I want to plot the resulting region. Is there a correct way of doing this?