# DFT, Square to Triangle and Related functions.

Cuthbert Nyack
The applet shows how the spectrum of a signal changes as the waveform changes from square to triangle and related functions.

eg parameters:-
(4.0, 0.0, 3.15, 6.26, 100, 0, 60, 10.0, 14.8, 0.1) 'square'
change a to 0.25
(4.0, a, 1.6, 7.77, 56, 0, 60, 150.0, 14.8, 0.2) 'square'
3rd harmonic reaches a minimum at a ~ 0.17, with wL = 250.0 the 5th harmonic reaches a minimum at a ~ 0.21.
(4.0, 0.25, 3.15, 6.26, 100, 0, 60, 10.0, 14.8, 0.1) 'triangle'
(4.0, 0.0, 3.15, 6.26, 100, 1, 60, 10.0, 14.8, 0.1) '+ve ramp'
change a to 0.25
(4.0, 0.25, 3.15, 6.26, 100, 1, 60, 10.0, 14.8, 0.1) '-ve ramp' with slope variable by a.
(4.0, 0.16 - 0.88, 3.15, 6.26, 100, 2, 60, 10.0, 14.8, 0.1) 'rectangle' with asymmetry variable by a.
(4.0, 0.0 - 0.25, 3.15, 6.26, 100, 3, 60, 10.0, 14.8, 0.1) 'staircase' with number of steps variable by a.
(4.0, 0.0 - 0.25, 3.15, 6.26, 100, 4, 60, 10.0, 14.8, 0.1) '+ve triangle pulse' with width variable by a.
(4.0, 0.25, 3.75, 6.5, 8, 4, 16, 10.0, 14.8, 1.7) '+ve triangle pulse' constant
(4.0, 0.0 - 0.25, 3.15, 6.26, 100, 5, 60, 10.0, 14.8, 0.1) '+ve and -ve triangle pulse' with width variable by a.
(4.0, 0.25, 3.86, 6.6, 8, 5, 16, 10.0, 14.8, 1.7) '+ve and -ve triangle pulse' constant?
(4.0, 0.0 - 0.25, 3.15, 6.26, 100, 6, 60, 10.0, 14.8, 0.1) 'exponential pulse' with rate of decay variable by a.
(4.0, 0.0 - 0.25, 3.15, 6.26, 100, 7, 60, 10.0, 14.8, 0.1) 'exponential pulse' with initial slope variable by a.