# lines to curves drawing problem

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Anas A.Salam on 5 Jun 2013
hello i have a problem with drawing curve on line or by other words
what i have: points on X-axis with their values on Y-axis as show in figure
what i need to do: draw curve between each two points (i don't want to show the figure as lines but as curves)
thank you

Kye Taylor on 5 Jun 2013
I assume you have the variables x and y which are vectors representing the values in the x-component and in the y-component of each point, respectively. Then, try this
% assuming x and y are your variables:
xValues = linspace(min(x),max(x));
yValues = interp1(x,y,xValues,'spline');
plot(x,y,xValues,yValues)
Anas A.Salam on 5 Jun 2013
thank you so much i tried your code and change some thing in it to have what i need thank you again :)

Mark on 5 Jun 2013
The problem is that MATLAB doesn't know what curve you want, since there is no data between the points you have. You either need more data resolution, or you can tell MATLAB to make a smooth curve by interpolating with a spline:
xNew = 0:0.1:160;
yNew = interp1(x,y,xNew,'spline');
plot(xNew,yNew)
However, remember that the smooth curve is made up by MATLAB, so it could be misleading to show smooth curves if there are not really any in reality.
Anas A.Salam on 5 Jun 2013
thank you so much :) i try your answer but the result was not like what i accepted :) any way thank you so much for your help :)