How do I create a BSFC contour map?

Hi,

I've managed to create a 3D plot using BSFC, speed and BMEP data:

figure

plot3(speed,BMEP,BSFC)

tri = delaunay(speed,BMEP);

h = trisurf(tri,speed,BMEP,BSFC);

shading interp

colorbar

I would however like to create a simple 2D contour map using the same data and have been unsuccessful. Can any one help?

The data used is:

speed = [1200 2400 2400 2400 3000 1800 1800];

BMEP = [1.70 1.30 2.55 4.22 4.99 4.25 1.71];

BSFC=[ 0.2927 0.3278 0.2530 0.2056 0.1834 0.2171 0.3224]

Any help would be appreciated.

[John D'Errico]

Please do not do this. it makes this question useless for anyone to learn from.

[Rena Berman]

(Answers Dev) Restored question.

Answer 1

[Chad Greene]

How's this? It uses John D'Errico's gridfit function.

% Input data: 
speed = [1200 2400 2400 2400 3000 1800 1800];
BMEP = [1.70 1.30 2.55 4.22 4.99 4.25 1.71];
BSFC=[ 0.2927 0.3278 0.2530 0.2056 0.1834 0.2171 0.3224];

% Create gridded data:
speedgrid = linspace(min(speed),max(speed),50); 
BMEPgrid = linspace(min(BMEP),max(BMEP),50); 
BSFCgrid = gridfit(speed,BMEP,BSFC,speedgrid,BMEPgrid);

% Plot: 
contour(speedgrid,BMEPgrid,BSFCgrid)
hold on
plot(speed,BMEP,'r*','markersize',12)
legend('contours','data points')

[Anjal Patel]

I tried doing this way, but it gives me an error saying, Undefined function or variable gridfit can anyone help me .

[Chad Greene]

You must download gridfit from the File Exchange site.

[Udaya kumar Manogarane]

I have the same doubt. I have my Rpm, Torque(Nm),BSFC(g/kwh). I used the gridfit code as well, which you attached in the above commment.But at the end, i am not getting my BSFC curve. I have attached my BSFC map. I dont know, why it look like worse or not similar like a normal BSFC map. Can anyone give me a solution for this.Thanks in advance