What I want to do is trying to get different values of p_y_given_x for different sigma2_n separately in each line? When I use append it gives me result in one array. But I want separate results for each 0.2 for p_y_given_x.
Is there any hint for me?
for sigma2_n in np.arange(0.2,0.9):
p_y_given_x= np.exp(-(y_new-alphabet[t])**2/2/sigma2_N)
the result should be like this
p_y_given_x1=
p_y_given_x2=
p_y_given_x3=
....
ummmmm.... actually maybe this helps f(x)=x+2, f(1)=1+2, f(2)=2+2 and etc, I want to use a for loop and define x inside it and for each iteration use one values of x and insert it inside the function and calculate the f(x), but i would like to get values of f(x) separately and compare them, for example like this:
f(1)
f(2)
f(3)(separately in different lines)
not like this in one array[f(1),f(2),f(3)] for the last case we can use append()
I am trying to write a histogram builder to construct a 2d histogram for my assignment work. This is [my code][1]:
def Build2DHistogramClassifier(X1,X2,T,B,x1min,x1max,x2min,x2max):
HF=np.zeros((B,B),dtype='int');#initialising a empty array of integer type
HM=np.zeros((B,B),dtype='int');
bin_row_indices=(np.round(((B-1)*(X1-x1min)/(x1max-x1min)))).astype('int32');"""this logic decides which bin the value goes into"""
bin_column_indices=(np.round(((B-1)*(X2-x2min)/(x2max-x2min)))).astype('int32');"""np.round-->applies the formula to all the values in the array"""
for i,(r,c) in enumerate(zip(bin_row_indices, bin_column_indices)):
"""enumerate-->if we put array or list into it gives output with index/count i """
if T[i]=='Female':
HF[r,c]+=1;
else:
HM[r,c]+=1;
return [HF, HM]
but the problem is that the results( count in each bin) i am getting is not matching the what i get from using hist2d function in numpy( i passed the same bin size)
i am sorry if my code is not in the right format. Please click on the hyperlink to a gist i created with the same code.
what is the mistake in my code?
how do i correct it?
thanks
By rounding when assigning to bins you are treating the bins as bin centers. The numpy convention is to use them as bin edges.
Remove the two calls to round() from your code and change B-1 to B. You should now get the same results with your function and with np.histogram2d.
I have the code mentioned below in matlab. I want to write all the 162 rows and 4 columns calculated into an excel file.
When i use xlswrite in the code i get only one row and 4 columns as the value of P gets overwritten in each iterative step.
If i use another loop inside the for loop the execution time increase drastically. Please help to least write the values of P into an array which i can later write into excel file(when i tried 'In an assignment A(I) = B, the number of elements in B and I must be the same' error appeared.)
please help
function FitSMC_BC
clc
% Parameters: P(1)=theta_S; P(2)=theta_r; P(3)=psib; P(4)=lamda;
smcdata=xlsread('asimdata');
nn=length(smcdata)-1;
for i=1:nn
psi=smcdata(:,1);
thetaObs=smcdata(:,i+1);
%Make an initial guess:
Pini=[0.5 0.1 -1 1.5];
P=fminsearch(#ObFun,Pini,[],psi,thetaObs);
disp(['result',num2str(i),': P=',num2str(P)]);
theta=Gettheta(P,psi);
end
function OF=ObFun(P,psi,thetaObs)
theta=Gettheta(P,psi);
OF=sqrt(mean((theta - thetaObs).^2));
function theta=Gettheta(P,psi)
SoilPars.theta_S=P(1);
SoilPars.theta_r=P(2);
SoilPars.psib=P(3);
SoilPars.lamda=P(4);
[theta]=thetaFun(psi,SoilPars);
function [theta]=thetaFun(psi,SoilPars)
theta_S=SoilPars.theta_S;
theta_r=SoilPars.theta_r;
psib=SoilPars.psib;
lamda=SoilPars.lamda;
theta=theta_r+((theta_S-theta_r)*((psib./psi).^lamda));
theta(psi>psib)=theta_S;
You can modify the P line with
P(i,:) = fminsearch(#ObFun,Pini,[],psi,thetaObs);
P will store each calculation (4 element vector) in a new line.
You may also initialise P before the for loop with P = nan(nn, 4);
Then write P in an Excel file using xlswrite.
I haven't studied your code in-depth, but as far as I can tell, you have two options:
Create a matrix P and use xlswrite on the entire matrix. This seems to me like the most reasonable approach.
Use xlswrite1 from the fileexchange in a loop. This will increase execution time a bit, but not nearly as much as using regular xlswrite as it is specially deigned to be used inside loops. The reason why it is so much faster is because it only opens and closes the Excel-file once, whereas the regular xlswrite opens and closes it every time you call the function.
You seem to know how to use indexing so I'm not sure why you're simply doing something like this:
P = zeros(size(smcdata,1),nn)
for i=1:nn
...
P(:,i) = fminsearch(#ObFun,Pini,[],psi,thetaObs);
disp(['result',num2str(i),': P=',num2str(P(:,i))]);
theta = Gettheta(P(:,i),psi); % Why is this here? Are you writing it to file too?
end
xlswrite('My_FileName.xls',P);
Or you could call xlswrite on each iteration of the loop (probably slower) and append the new data using something like this:
for i=1:nn
...
P = fminsearch(#ObFun,Pini,[],psi,thetaObs);
disp(['result',num2str(i),': P=',num2str(P)]);
theta = Gettheta(P,psi); % Why is this here? Are you writing it to file too?
xlswrite('My_FileName.xls',P,1,['A' int2str((i-1)*size(P,2)+1)]);
end
Of course your code isn't runnable so you'll have to debug any other little errors. Also, since smcdata seems to be a matrix rather than a vector, you should be careful using length with it. You probably should use size.
Question : Is there a way to have direct access to a specific cell in vtkPolyData structure?
I'm using vtkPolyData to store sets of lines, say L.
Currently, I'm using GetLines() to know the number of lines in L. Then, I have to use GetNextCell to go through this set of lines using a "while" loop.
Current code is something like:
vtkSmartPointer<vtkPolyData> a;
...
vtkSmartPointer<vtkCellArray> lines = a->GetLines();
...
while(lines->GetNextCell(numberOfPoints, pointIds) != 0)
-> I'd like to be able to work directly on a specific line by doing something like:
myline = a[10];
doSomething(myline);
you could get an access to a specific cell using vtkDataSet::GetCell(vtkIdType cellId) function
I asked another question that wasnt answered, which led me to this question. I have a for loop that makes an array of the samples in a sound file. I do it to two files, and try to combine them in a third file. However, the array of values only exists within the for loop so I can't use the values I need in the third because to I need to access the array of samples in the third file using a for loop as well. A nested for loop doesnt seem to make sense in this situation.
Sorry forgot to mention I'm using python.
This is the chunk of the code that confuses me.
for index in getSamples(sound1):
v1 = getSampleValue(index)
for index in getSamples(sound2):
v2 = getSampleValue(index)
for index in getSamples(sound3):
setSampleValue(index, v1+v2)
So the code basically gets all the samples from sound1, all the samples from sound 2, and tries to set the samples in sound3(same length as both sounds) to the combination of each sample at each index.
However when this only plays/explores a blank sound for sound 3. I think the problem is that v1 and v2 are only equal to the values of the entire array within the individual for loops.
in order to use a variable outside of the loop to reference the array, you need to initialize that variable outside of the loops. This gives you a reference to the array.
var array = new Array();
for (int x=0; x<sample.length(); x++) {
//do stuff in the loop to 'array' variable
}
//do what you want with 'array' after the loop
Not sure what are you intend to do since you don't provide any chunks of code.
But basically, yes you can. I'll write something in php:
$myarray = array(); //init the array
for($i=1; $i<10; $i++){
//do something with myarray
}
//you can use myarray here
The point is : declare the "whatever you want to use" outside the loop before the loop started