How to plot a piecewise function on Matlab?

Question

I am unable to plot this graph. Any one please help me to plot?

f = double(X<20).* (0) + ...
double(and(X>=20,X<35)).* ((X-20)./15) + ...
double(X>=35).*(1);
g = double(X<20).* (1) + ...
double(and(X>=20,X<35)).* ((35-(X))./(15)) + ...
double(X>=35).*(0);
figure; 
plot(X,f,'r','linewidth',2);
hold on ;
plot(X,g,'b','linewidth',2); xlabel('X');grid on;xticks(2:1:10); 
legnd('f(x)','g(x)')

In other words, I want to plot the following functions:

Answer 1

You may use MATLAB's function handlers.

clear();
close('all');

% Parameters
gridMinVal = -10;
gridMaxVal = 50;
gridNumPts = 10000;

% Grid
vX = linspace(gridMinVal, gridMaxVal, gridNumPts);
vX = vX(:);

% Functions
hFx = @(vX) (0 .* (vX < 20)) + (((vX - 20) / 15) .* ((vX >= 20) & (vX < 35))) + (1 .* (vX >= 35));
hGx = @(vX) (1 .* (vX < 20)) + (((35 - vX) / 15) .* ((vX >= 20) & (vX < 35))) + (0 .* (vX >= 35));

hF = figure();
hA = axes(hF);
set(hA, 'NextPlot', 'add');
plot(vX, hFx(vX), 'LineWidth', 3, 'DisplayName', 'f(x)');
plot(vX, hGx(vX), 'LineWidth', 3, 'DisplayName', 'g(x)');
set(get(hA, 'Title'), 'String', {['Piece Wise Functions']});
set(get(hA, 'XLabel'), 'String', {['x']});
set(get(hA, 'YLabel'), 'String', {['y']});
legend();