2D Line Interpolation

Hi

I have data in 2D as a line data (example given as)

y1 x1 y2 x2 val err

36.97 126.5 36.79 126.45 394.94 1.79

36.98 126.4 36.79 126.45 179.59 0.75

37 126.65 36.55 126.64 82.64 0.35

37.4 127.21 37.35 126.7 379.76 1.53

34.75 127.17 34.4 126.7 172.95 0.73

37.45 126.82 37.89 126.77 401.29 1.6

36.98 126.4 37.08 126.77 1168.43 4.97

37.4 127.21 37.89 126.77 114.6 0.52

35.32 127.45 34.98 126.9 289.95 1.19

36.97 126.5 37.49 126.92 3462.07 15.01

37.16 127.52 37.49 126.92 151.54 0.61

37.4 127.21 37.49 126.92 167.04 0.69

37.16 127.52 37.49 126.92 240.72 1.01

36.2 127.48 36.27 126.92 235.94 0.95

36.35 127.2 36.27 126.92 155.95 0.63

35.27 127.42 35.49 126.93 1002.81 4.37

35.32 127.45 35.49 126.93 756.71 3.24

36.97 126.5 37.28 126.98 262.64 1.16

37.4 127.21 37.28 126.98 118 0.49

36.9 126.59 37.28 126.98 114.9 0.49

35.27 127.42 35.16 126.99 180.78 0.61

I need to interpolate the data. (The gridded data must be shown within the limits as defined by the user as Y (35.5 - 36.5) and X (128.5 - 129.5)

How I can do it. Waiting for your kind reply.

[KSSV]

It is not possible to achieve what you want....the given points lie somewhere and the grid extents for which you want to interpolate are somehwere. Figure atatched.

[Muhammad Zafar Iqbal]

Hi KSSV

Is it possible to make grid at that place according to data?

[KSSV]

But what is the corresponding val for (x1,y1) and (x2,y2) data? Is val and err are same?

[Muhammad Zafar Iqbal]

val is the corresponding value and err is the standard error

[Muhammad Zafar Iqbal]

Dear KSSV

Thanks for your kind help.

I want to ask if we have only two lines as

140.5 35.25 140.75 35.5 10 1

140.25 35.5 140.5 35.75 5 2

What we have to change as when I run for only two lines the error message is

"Matrix dimensions must agree."

Thanks

Answer 1

[KSSV]

data = [36.97  126.5  36.79  126.45  394.94  1.79 
 36.98  126.4  36.79  126.45  179.59  0.75 
 37  126.65  36.55  126.64  82.64  0.35 
 37.4  127.21  37.35  126.7  379.76  1.53 
 34.75  127.17  34.4  126.7  172.95  0.73 
 37.45  126.82  37.89  126.77  401.29  1.6 
 36.98  126.4  37.08  126.77  1168.43  4.97 
 37.4  127.21  37.89  126.77  114.6  0.52 
 35.32  127.45  34.98  126.9  289.95  1.19 
 36.97  126.5  37.49  126.92  3462.07  15.01 
 37.16  127.52  37.49  126.92  151.54  0.61 
 37.4  127.21  37.49  126.92  167.04  0.69 
 37.16  127.52  37.49  126.92  240.72  1.01 
 36.2  127.48  36.27  126.92  235.94  0.95 
 36.35  127.2  36.27  126.92  155.95  0.63 
 35.27  127.42  35.49  126.93  1002.81  4.37 
 35.32  127.45  35.49  126.93  756.71  3.24 
 36.97  126.5  37.28  126.98  262.64  1.16 
 37.4  127.21  37.28  126.98  118  0.49 
 36.9  126.59  37.28  126.98  114.9  0.49 
 35.27  127.42  35.16  126.99  180.78  0.61 ] ;
 
 y1 = data(:,1) ; y2 = data(:,3) ; 
 x1 = data(:,2) ; x2 = data(:,4) ;
val = data(:,5) ; err = data(:,6) ; 

m = 100 ; 
xi = linspace(min(x1),max(x1),m) ;  
yi = linspace(min(y1),max(y1),m) ;  
[X,Y] = meshgrid(xi,yi) ; 

V = griddata(x1,y1,val,X,Y) ; 
pcolor(X,Y,V)
shading interp 

[Muhammad Zafar Iqbal]

Dear KSSV

I need your more help

for the same data, I need node values if possible.

Waiting here for your kind reply.