I'm writing a program to play blackjack and one of the functions calculates the score. It takes in an input which is a structure array of cards and one of the attributes is value (for an ace the value is 11). My function is supposed to determine if the total of the values is over 21 and if 1 of the cards is an ace, then the ace's value is changed to 1. Can anyone help me figure this out please?
for index=1:length(input)
if(input(input).value == 11)
input(index).value = 1;
end;
end;
You're not actually summing the cards in your original snippet. You also seem to have a typo in input(input), I think this should be input(index). If you wanted to do it with a for loop like you have, you'd do something like this:
total = 0;
for index=1:length(input)
if(input(index).value == 11)
input(index).value = 1;
end;
total = total + input(index);
end;
The more MATLAB way of doing things would be to avoid loops by using the sum in-built command.
Related
I have an array of 1 x 400, where all element values are above 1500. However, I have some elements that have values<50 which are wrong measures and I would like to have the mean of the elements before and after the wrong measured data points and replace it in the main array.
For instance, element number 17 is below 50 so I want to take the mean of elements 16 and 18 and replace element 17 with the new mean.
Can someone help me, please? many thanks in advance.
No language is specified in the question, but for Python you could work with List Comprehension:
# array with 400 values, some of which are incorrect
arr = [...]
arr = [arr[i] if arr[i] >= 50 else (arr[i-1]+arr[i+1])/2 for i in range(len(arr))]
That is, if arr[i] is less than 50, it'll be replaced by the average value of the element before and after it. There are two issues with this approach.
If i is the first or last element, then one of the two values will be undefined, and no mean can be obtained. This can be fixed by just using the value of the available neighbour, as specified below
If two values in a row are very low, the leftmost one will use the rightmost one to calculate its value, which will result in a very low value. This is a problem that may not occur for you in practice, but it is an inherent result of the way you wish to recalculate values, and you might want to keep it in mind.
Improved version, keeping in mind the edge cases:
# don't alter the first and last item, even if they're low
arr = [arr[i] if arr[i] >= 50 or i == 0 or i+1 == len(arr) else (arr[i-1]+arr[i+1])/2 for i in range(len(arr))]
# replace the first and last element if needed
if arr[0] < 50:
arr[0] = arr[1]
if arr[len(arr)-1] < 50:
arr[len(arr)-1] = arr[len(arr)-2]
I hope this answer was useful for you, even if you intend to use another language or framework than python.
I have a data (matrix) with 3 columns : DATA=[ID , DATE, Value]
I want to filter my data by ID for example DATAid1= DATA where ID==1 and so on ..
for that I write this code in MATLAB
load calibrage_capteur.mat
data = [ID ,DATE , Valeur]
minid = min(data(:,1));
maxid = max(data(:,1));
for i=minid:maxid
ind=find(data(:,1) == i)
dataID = [ID(ind) ,DATE(ind) , Valeur(ind)]
end
As a result he register the last value in this example the max ID=31 so he register dataId31. Now I need how to save the variable each iteration. How can I do this?
You will want to use a cell array to hold your data rather than saving them as independent variables that are named based upon the ID.
data_by_ID = cell();
ids = minid:maxid;
for k = 1:numel(ids)
data_by_ID{k} = data(data(:,1) == ids(k),:);
end
Really though, depending on what you're doing with it, you can use data all of the time since all operations are going to be faster on a numeric matrix than they are on a cell array.
%// Do stuff with data ID = 10
do_stuff(data(data(:,1) == 10, :));
Update
If you absolutely must name your variables you could do the following (but please don't do this and use one of the methods above).
for k = 1:numel(ids)
eval(['dataId', num2str(ids(k)), '= data(k,:);']);
end
Your question is a bit unclear but it sounds like you simply want to save the result at each iteration of the for loop.
I'm assuming min and max id are arbitrary and not necessarily the variable you are trying to index on.
kk = min_id:max_id;
dataID=nan(size(kk));
for ii = 1:numel(kk)
ind=find(data(:,1) == kk(ii))
dataID(kk) = [ID(ind) ,DATE(ind) , Valeur(ind)]
end
This is better than indexing by min_id or max_id since it isn't clear that min_id starts at at 1 (maybe it starts at 0, or something else.)
This is quite a simple issue, but I've been struggling with it. sortedd and sortedfinal_d are 8 x 1000 Matrices and I am using the loop below to check if any of the elements in sortedfinal_d lies between two consecutive elements of sortedd, in terms of magnitude. I'm doing this along each row. overall_p is a 8 x 1000 Matrix as well, but at the end of this process I end up having final_p as a Matrix of Zeros. I don't know why this is.
for k=2:1000
for s=1:1000
for j=1:8
if sortedd(j,k) > sortedfinal_d(j,s) && sortedfinal_d(j,s) > sortedd(j,k-1)
final_p(j,s) = overall_p(j,k);
end
end
end
end
EDIT: Added data for the inputs as shown below:
sortedd (first four columns) =
0.219977361620113 0.219996752039812 0.220344444223787 0.220593274018691
0.272807483153955 0.273682693068593 0.273846498221277 0.274060049642900
0.327201460264565 0.327375792227635 0.327572790857546 0.327856448530021
0.380389118311424 0.380845274148177 0.380893687870765 0.381015090963159
0.434832574575088 0.434860658844550 0.435021604722982 0.435119929919457
0.487119089589798 0.488128501559782 0.488207451439073 0.488430455768512
0.540652551559395 0.541303305046034 0.542195194863130 0.542234381085921
0.595254195563241 0.595296064375604 0.595376090156252 0.595377962767971
sortedfinal_d =
0.182086792394190 0.182406508309366 0.182406508309366 0.182808976400818
0.233058295607543 0.233058295607543 0.233158455616954 0.233158455616954
0.286243848617693 0.286357973626582 0.286918095670684 0.287393171241241
0.336938335090164 0.336938335090164 0.337094505106945 0.337669618738100
0.390287818652551 0.390567879874952 0.390567879874952 0.390670502700602
0.446995120903824 0.447270251510681 0.447452123072880 0.447597175111267
0.501060785098551 0.501060785098551 0.501060785098551 0.501060785098551
0.551311219045087 0.551463923687602 0.551463923687602 0.551653815175502
Thanks a lot
Do you have to use loops to accomplish this?
matching_d = sortedfinal_d(:,1:end-1) < sortedd(:,2:end) ...
& sortedd(:,2:end) < sortedfinal_d(:,2:end);
final_p(matching_d) = overall_p(matching_d);
If you can show us a small sample input (say, 1x5 versions of sortedd and sortedfinal_d) and output (the corresponding matching_d) it would be easier for us to help troubleshoot.
If i set your matrices to random numbers, final_p does return some numbers.
So your code works as is. Post your dataset or at least describe the dataset in some detail, this will make it much easier to diagnose the problem.
I have reduced 1000 down to 10 and re-ordered the iteration variables to i, j, k to make it easier to follow:
sortedd = rand(8, 10);
sortedfinal_d = rand(8, 10);
overall_p = rand(8, 10);
for i=2:10
for j=1:10
for k=1:8
if sortedd(k,i) > sortedfinal_d(k,j) && sortedfinal_d(k,j) > sortedd(k,i-1)
final_p(k,j) = overall_p(k,i);
end
end
end
end
final_p
I am new to Scala and am implementing a Sudoku solver. I have a method which returns the set of all possible values a particular element int the grid can take and it works. However, I think that there is a much better way to do this. The problem arises when I try to check the values of other elements in the same block. Is there any other way (than the one shown below) I can find a relationship between the row, column and block to result in cleaner code?
Note that r and c are the row and column indices, respectively, and are given as parameters to the function.
val i=
if(r==0|r==1|r==2){
if(c==0||c==1||c==2)
0
else if(c==3|c==4|c==5)
1
else
2
} else if (r==3|r==4|r==5){
if(c==0||c==1||c==2)
3
else if(c==3||c==4||c==5)
4
else
5
} else {
if(c==0||c==1||c==2)
6
else if(c==3||c==4||c==5)
7
else
8
}
def i(r:Int,c:Int) = r/3*3 + c/3
Although you'll probably want to find a better name/ add comments, it's not really the most intuitive function...
I have this code, but there must be a better efficient to write it:
rt= RealTrans;
rtsize=size(rt);
rtrows=rtsize(1);
Relative_Axis_Moves=[rt(1,1) rt(1,2) rt(1,3) rt(1,4) rt(1,5);
rt(2:rtrows,1)-rt(1:rtrows-1,1) rt(2:rtrows,2)-rt(1:rtrows-1,2)
rt(2:rtrows,3)-rt(1:rtrows-1,3) rt(2:rtrows,4)-rt(1:rtrows-1,4)
rt(2:rtrows,5)-rt(1:rtrows-1,5)];
There are two rows in the matrix. The first row ends at rt(1,5).
I also have the following code:
p1size=size(p1);
p1rows=p1size(1);
flank_edge_point=[0 0 0; p1(2:p1rows,2)-p1(1:p1rows-1,2) xy(2:p1rows,1)-xy(1:p1rows-1,1) xy(2:p1rows,2)-xy(1:p1rows-1,2); 0 0 xy(p1rows,2)];
How do i get xy(p1rows,2) value in matlab without p1rows?
I also have the code below which relies on the number of rows:
RAMrow=size(Relative_Axis_Moves);
RAMrow=RAMrow(1);
for i=1:RAMrow
L(i)= norm(Relative_Axis_Moves(i,:));
end
L=L';
L(RAMrow+1)= 0;
Any way to write this code more succinctly and efficiently would be greatly appreciated.
Most likely, there will be more than two rows in Relative_Axis_Moves, since the differences in the second row evaluate to arrays.
Anyway, a compact way of writing this is
Relative_Axis_Moves = [RealTrans(1,1:5);diff(RealTrans(:,1:5),1,1)];