Flag of Bangladesh — construction sheet
Own work. Geometry as described in 
People’s Bangladesh National Anthem, Flag and Emblem Order, 1972.

When the length of the Flag is 10′ –
(a) its width will be 6′;
(b) the radius of the red circle in the Flag will be 2′;
(c) if a national perpendicular is drawn at a point 4 1⁄2′ from the left hand of the length of the Flag and a horizontal line is drawn from the middle of its width, the centre of the red circle shall be at the point of intersection of these two lines.

— Flag and Emblem Order, 1972, in: Sechdule 2, Section 2

The term "national perpendicular" used in the Flag and Emblem Order is assumed to mean "vertical line".
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