# MatLab by wanghonghx

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```									MatLab

-et krasjkurs
www.stud.ntnu.no/~gjerding/data
>> well

well =

depth:   [18163x1 double]
Vp:   [18163x1 double]
Vs:   [18163x1 double]
rho:   [18163x1 double]
name:   {1x9 cell}
top:   [1x9 double]
bottom:   [1x9 double]
   Plott Vp mot rho for ’Ty’ formasjonen og trekk
en regresjonslinje

Vp   rho
1    1
Top Ty
2    2
.    .
.    .
Bunn Ty

n    n
Gardner et al. (1974):              0.31Vp.25

Brønn:                              aVp.25          a?

rho

Vp

 V  
1
4

           
p ,i           i
     aV   .25 2
 min                a   i

V
p                                                 1
4
p ,i
i
 V  
1
4
close all; clear                                                                                     p ,i           i

V
1
4
p ,i
frm = 4;                                                                                         i
id = find( well.depth >= well.top(frm) & well.depth <= well.bottom(frm) ) ;

% ...the regression coefficients
a = sum( well.Vp(id).^.25.* well.rho(id) ) ...                                      #    depth                Vp        Rh
/sum(( well.Vp(id) .^.25).^2);                                                                                      o
x = [ min(well.Vp(id)) : max(well.Vp(id)) ];                                        1    .                    .         .
Top ty
2    .                    .         .
.    .
id=
.
subplot(2,2,1)
hold on                                                                   Bunn ty                             .         .
plot( well.Vp(id) , well.rho(id) ,'r.' )                                            n    n                    n         n
legend('well',4)
plot(x,a*x.^.25,'b')

xlabel('Vp [m/s]'); ylabel('rho [g/cc]');
title(well.name(frm))
axis tight
grid

str = num2str(a);
text(2380,2.20,strcat('Gardner: rho = ',str,'Vp^0^.^2^5'))
Plotte seismikk
Seiswiggle(data)

mesh(data)
view(60,50)
View(0,90)
Fourier Transform
Andre ting
   SEGY => MatLab
 www.stud.ntnu.no/~gjerding

 MatLab – Fortran / C++
 MatLab – unix
 Perl, awk, sed etc.
 unix

```
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