Hot to do the math for plotting ?

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Hot to do the math for plotting ?

 Hi, looks like I'm not only too numb for octave but for googleing too. I get only links to the plotting documentation. Here's the script: %% plot_3_functions - Plots three functions with range %% and number of points given by user. Interval = input('Enter interval as vector [lower upper]: '); numPoints = input('How many points to plot: '); x = linspace(Interval(1),Interval(2),numPoints); F = 3.*(x).^2.-2*sin(x);     % 3x^2-2sin(x) G = sqrt(abs(x.-3));         % sqrt(|x-3|) H = exp(-2.*x.*x);           % e^(-2x^2) plot(x,F,'x',G,'*',H,'o'); %% axis([Interval(1) Interval(2) -2 10]); xlim([Interval(1), Interval(2)]); ylim([-2, 10]); xlabel("x-axis"); ylabel("y-axis"); title("Exercise 3.3.4"); legend("3x^2-2sin(x)", "sqrt(|x|)", "e^-2x^2"); %% saveas(gca,'fonctions.pdf','pdf'); I get 3 plots and the square function looks good but the Euler and Square-root functions G and H are plain wrong (checked with gnuplot). So what am I doing wrong here ? Regards, Stephan _______________________________________________ Help-octave mailing list [hidden email] https://lists.gnu.org/mailman/listinfo/help-octave
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Re: Hot to do the math for plotting ?

 On Tue, Jan 16, 2018 at 10:50 AM, Stephan Goldenberg wrote:Hi, looks like I'm not only too numb for octave but for googleing too. I get only links to the plotting documentation. Here's the script: %% plot_3_functions - Plots three functions with range %% and number of points given by user. Interval = input('Enter interval as vector [lower upper]: '); numPoints = input('How many points to plot: '); x = linspace(Interval(1),Interval(2),numPoints); F = 3.*(x).^2.-2*sin(x);     % 3x^2-2sin(x) G = sqrt(abs(x.-3));         % sqrt(|x-3|) H = exp(-2.*x.*x);           % e^(-2x^2) plot(x,F,'x',G,'*',H,'o'); %% axis([Interval(1) Interval(2) -2 10]); xlim([Interval(1), Interval(2)]); ylim([-2, 10]); xlabel("x-axis"); ylabel("y-axis"); title("Exercise 3.3.4"); legend("3x^2-2sin(x)", "sqrt(|x|)", "e^-2x^2"); %% saveas(gca,'fonctions.pdf','pdf'); I get 3 plots and the square function looks good but the Euler and Square-root functions G and H are plain wrong (checked with gnuplot). So what am I doing wrong here ? Regards, Stephan _______________________________________________ Help-octave mailing list [hidden email] https://lists.gnu.org/mailman/listinfo/help-octave -- DAShere is a start for you --- it still needs some fixing.%% plot_3_functions - Plots three functions with range%% and number of points given by user.Interval = input('Enter interval as vector [lower upper]: ');numPoints = input('How many points to plot: ');x = linspace(Interval(1),Interval(2),numPoints);F = 3.*(x).^2.-2*sin(x);     % 3x^2-2sin(x)G = sqrt(abs(x.-3));         % sqrt(|x-3|)H = exp(-2.*x.*x);           % e^(-2x^2) subplot(3,1,1)plot(x,F);%% axis([Interval(1) Interval(2) -2 10]);xlim([Interval(1), Interval(2)]);#ylim([-2, 10]);xlabel("x-axis");ylabel("y-axis");title("Exercise 3.3.4");legend("3x^2-2sin(x)", "sqrt(|x|)", "e^-2x^2");%% saveas(gca,'fonctions.pdf','pdf');2 4 subplot(3,1,2) plot(x,G);%% axis([Interval(1) Interval(2) -2 10]);xlim([Interval(1), Interval(2)]);#ylim([-2, 10]);xlabel("x-axis");ylabel("y-axis");title("Exercise 3.3.4");legend("3x^2-2sin(x)", "sqrt(|x|)", "e^-2x^2");   subplot(3,1,3)  plot(x,H);%% axis([Interval(1) Interval(2) -2 10]);xlim([Interval(1), Interval(2)]);#ylim([-2, 10]);xlabel("x-axis");ylabel("y-axis");title("Exercise 3.3.4");legend("3x^2-2sin(x)", "sqrt(|x|)", "e^-2x^2"); _______________________________________________ Help-octave mailing list [hidden email] https://lists.gnu.org/mailman/listinfo/help-octave