Pyxplot 
Examples  Pythagoras theorem 
Using lines, boxes and text labels for geometric construction In this example, Pyxplot's arrow and text commands are used to produce a diagram illustrating Euclid's proof of Pythagoras' theorem. Scriptset unit angle nodimensionless set multiplot ; set nodisplay # Lengths of three sides of triangle AB = 2*unit(cm) AC = 4*unit(cm) BC = hypot(AC, AB) # Hypotenuse CBA = atan2(AC, AB) # Angle CBA # Positions of three corners of triangle Bx = 0*unit(cm) ; By = 0*unit(cm) # The origin Cx = Bx + BC ; Cy = By Ax = Bx + AB*cos(CBA) ; Ay = By + AB*sin(CBA) # Positions of constructed points Dx = Bx ; Dy = BC Lx = Ax ; Ly = Dy Ex = Cx ; Ey = Dy Hx = Bx + (AB + AC) * cos(CBA) Hy = By + (AB + AC) * sin(CBA) Kx = Cx + ( AC) * cos(CBA) Ky = Cy + ( AC) * sin(CBA) Fx = Bx + AB*cos(CBA+90*unit(deg)) Fy = By + AB*sin(CBA+90*unit(deg)) Gx = Ax + AB*cos(CBA+90*unit(deg)) Gy = Ay + AB*sin(CBA+90*unit(deg)) # Construct diagram box from Dx,Dy to Cx,Cy with fillcol gray50 box at Ax,Ay width AC height AC rot CBA90*unit(deg) with fillcol gray50 box at Bx,By width AB height AB rot CBA with fillcol gray50 line from Bx,By to Kx,Ky line from Fx,Fy to Cx,Cy line from Ax,Ay to Dx,Dy line from Ax,Ay to Lx,Ly line from Ax,Ay to Ex,Ey # Label diagram set fontsize 1.3 TG = 0.5*unit(mm) # Gap left between labels and figure text "A" at Ax,Ay gap TG*5 hal c val b text "B" at Bx,By gap TG hal r val t text "C" at Cx,Cy gap TG hal l val t text "D" at Dx,Dy gap TG hal c val t text "E" at Ex,Ey gap TG hal c val t text "F" at Fx,Fy gap TG hal r val c text "G" at Gx,Gy gap TG hal c val b text "H" at Hx,Hy gap TG hal c val b text "K" at Kx,Ky gap TG hal l val c text "L" at Lx,Ly gap TG hal c val t # Display diagram set display ; refresh
