How to convert this Matlab script in Igor

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Thu, 08/05/2010 - 04:38 am

Hi all:

I am relative a new Igor user and I am trying to make a Igor program that can do the following:

%% Given Data

k=0.39761; %Equivalent k

%% Approach Curves Data Sets

DATA2=load('C:\...\defl_ext.txt'); %collected Deflection from a dynamic approach curve[m]
DATA3=load('C:\...LVDT_ext.txt'); %Z Piezo Position [m]

% Filter
DATA2 = smooth(DATA2,15);

Fts0=zeros(n,1);
dgap=zeros(n,1);
Fts0new=zeros(n,1);

Zp=DATA3;

for i=1:n;
Fts0(i,1)=k.*DATA2(i,1);
end

%%Convert F-Z to F-d (nN vs. nm)

for i=1:n;

dgap(i,1)=-Zp(i,1).*10^9-DATA2(i,1); %nm
Fts0new(i,1)=Fts0(i,1).*10^9; %nN

end

%Find minimum force value (app), shift tip-sample distance

Fts0min = min(Fts0);
gapp = dgap;
ind=find(Fts0min);
gapp_min=dgap(ind,1);

for i=1:n
dgap(i,1)=-(dgap(i,1)-gapp_min);
end

plot(dgap,Fts0new,'-b')

It will be really appreciated if someone can give me some ideas of how to convert this to Igor.

Thanks:
Alexander Cartagena
Hopefully someone that knows Matlab will reply.

But as a non-Matlab person, I am left wondering:

What is n and where did it come from?

What is that ... stuff in the file path?

What does the .* syntax mean?

August 5, 2010 at 07:49 am - Permalink

I didn't test this, but something like (and you need to declare/define some of the other variables, like n):

// Given Data
variable k=0.39761 // Equivalent k

// Approach Curves Data Sets

newpath /o myData "C:someFolder:someSubFolder"
loadwaves /j/n=DATA2/p=myData "defl_ext.txt" //collected Deflection from a dynamic approach curve[m]
loadwaves /j/n=DATA3/p=myData ".LVDT_ext.txt" // %Z Piezo Position [m]
wave DATA2,DATA3

// Filter
smooth 15,DATA2

make /o/n=(n) Fts0=0,dgap=0,Fts0new=0

duplicate /o DATA3,Zp

Fts0=k*DATA2

// Convert F-Z to F-d (nN vs. nm)
dgap=-Zp*10^9-DATA2 // %nm
Fts0new=Fts0*10^9 // %nN

// Find minimum force value (app), shift tip-sample distance
wavestats /q Fts0
duplicate /o gapp,dgap
variable gapp_min=dgap(v_minloc,1)
     
dgap=gapp_min-dgap
     
display Fts0new vs dgap

August 5, 2010 at 04:59 pm - Permalink