Convert Cell to an Array - arrays

i have a cell array with dimensions 1x16384 consists of 16384 numbers.
I tried using cell2mat(), but i get one element with all those numbers in it.
How do i convert it to an array with 1x16384 dimension.
Assuming B= cell2mat(A);
A looks like;
Columns 16382 through 16384
'15.849' '16.337' '14.872'
where as B looks like;
B =
-8.921-8.433-2.5745.23911.58714.02811.5876.7041.821-1.109-2.085-1.5970.3562.
console ;
class(A), class(A{1}), size(A), size(A{1})
ans =
cell
ans =
char
ans =
1 16384
ans =
1 6
For mcve,
Csv input file
DELIMITER = ' ';
HEADERLINES = 3;
% Import the file
newData1 = importdata('C:\Python34\co2a0000364.csv', DELIMITER, HEADERLINES);
% Create new variables in the base workspace from those fields.
vars = fieldnames(newData1);
for i = 1:length(vars)
assignin('base', vars{i}, newData1.(vars{i}));
end
new = textdata(6:16452,4);
A = new;
for z = 1:63
A(i*257)=[];
end
B = A'
A= B;
A= cell2mat(B)
B= A

You way of importing data is quite clumsy. I invite you to read the textscan function documentation, which allows much more flexibility in importing mixed data type (text and numeric data).
I propose you another way of importing, which uses textscan:
%% // Import only the 4th column of data
fid = fopen('co2a0000364.csv') ;
M = textscan( fid , '%*s%*s%*s%f' , 'Delimiter',' ' , 'HeaderLines',4) ;
fclose(fid) ;
M = cell2mat(M) ;
%% // reshape to have each channel in its own colum
M = reshape( M , 257 , [] ) ;
%% // Delete the channel number from the data table
M(1,:) = [] ;
This will give you a nice 256*64 matrix, containing the data for each of the 64 channels in one column.
if you really want them all in sequence in one column, just add:
M = M(:) ;
to the end of the code.
Explanation note: the textscan format specifier I use: '%*s%*s%*s%f' tells the function to read 4 elements per line:
- 3x strings : %s
- 1x floating point number: %f
adding the character * in the format specifier (for example %*s) for an element tells the function to ignore the element, so it does not put it into the output.

Related

array processing with different indices and missing values in SAS

have is a sas data set with 4 variables: an id and variables storing info on all the activities a respondent shares with 3 different members of a team they're on. There are 4 different activity types, identified by the numbers populating in the :_activities vars for each player (p1 to p3). Below are the first 5 obs:
id p1_activities p2_activities p3_activities
A 1,2,3,4 1,3
B 1,3 1,2,3 1,2,3
C 1,2,3 1,2,3
D 1,2,3
E 1,2,3 1
Consider respondent A: they share all 4 activities with player 1 on their team, and activities 1 and 3 with player 2 on their team. I need to create flags for each player position and each activity. For example, a new numeric variable p1_act2_flag should equal 1 for all respondents who have a value of 2 appearing in the p1_activities character variable. Here are the first 6 variables I need to create out of the 12 total for the data shown:
p1_act1_flag p1_act2_flag p1_act3_flag p1_act4_flag p2_act1_flag p2_act2_flag …
1 1 1 1 1 0 …
1 0 1 0 1 1 …
. . . . 1 1 …
. . . . 1 1 …
1 1 1 0 . . …
I do this now by initializing all of the variable names in a length statement, then writing a ton if-then statements. I want to use far fewer lines of code, but my array logic is incorrect. Here's how I try to create the flags for player 1:
data want;
length p1_act1_flg p1_act2_flg p1_act3_flg p1_act4_flg
p2_act1_flg p2_act2_flg p2_act3_flg p2_act4_flg
p3_act1_flg p3_act2_flg p3_act3_flg p3_act4_flg
p4_act1_flg p4_act2_flg p4_act3_flg p4_act4_flg 8.0;
set have;
array plracts {*} p1_activities p2_activities p3_activities;
array p1actflg {*} p1_act1_flg p1_act2_flg p1_act3_flg p1_act4_flg;
array p2actflg {*} p2_act1_flg p2_act2_flg p2_act3_flg p2_act4_flg;
array p3actflg {*} p3_act1_flg p3_act2_flg p3_act3_flg p3_act4_flg;
array p4actflg {*} p4_act1_flg p4_act2_flg p4_act3_flg p4_act4_flg;
do i=1 to dim(plracts);
do j=1 to dim(p1actflg);
if find(plracts{i}, cats(put(j, $12.))) then p1actflg{j}=1;
else if missing(plracts{i}) then p1actflg{j}=.;
else p1actflg{j}=0;
end;
end;
*do this again for the other p#actflg arrays;
run;
My "array subscript is out of range" because of the different lengths of the player and activity arrays, but nesting in different do-loops would result in me writing many more lines of code than a wallpaper solution.
How would you do this more systematically, and/or in far fewer lines of code?
Not sure why you are processing 4 activities for flags when there are only 3.
Some ideas:
Refactoring the column names to numbered suffixes would reduce some of the wallpaper effect.
activities_p1-activities_p3
Refactoring the flag column names to number suffixes
flag_p1_1-flag_p1_4
flag_p2_1-flag_p2_4
flag_p3_1-flag_p3_4
Use DIM to stay within array bounds.
Use two dimensional array for flags
Use direct addressing of items to be flagged
Add error checking
Not fewer, but perhaps more robust ?
This code examines each item in the activities list as opposed to seeking presence of a specific items (1..4):
data want;
set have;
array activities
activities_p1-activities_p3
;
array flags(3,4)
flag_p1_1-flag_p1_4
flag_p2_1-flag_p2_4
flag_p3_1-flag_p3_4
;
do i = 1 to dim(activites);
if missing(activities[i]) then continue; %* skip;
do j = 1 by 1;
item = scan ( activities[i], j, ',' );
if missing(item) then leave; %* no more items in csv list;
item_num = input (item,?1.);
if missing(item_num) then continue; %* skip, csv item is not a number;
if item_num > hbound(flags,2) or item_num < lbound(flags,2) then do;
put 'WARNING:' item_num 'is invalid for flagging';
continue; %* skip, csv item is missing, 0, negative or exceeds 4;
end;
flags (i, item_num) = 1;
end;
* backfill zeroes where flag not assigned;
do j = 1 to hbound(flags,2);
flags (i, item_num) = sum (0, flags (i, item_num)); %* sum() handles missing values;
end;
end;
Here is the same processing, but only searching for specific items to be flagged:
data have; length id activities_p1-activities_p3 $20;input
id activities_p1-activities_p3 ; datalines;
A 1,2,3,4 1,3 .
B 1,3 1,2,3 1,2,3
C . 1,2,3 1,2,3
D . 1,2,3 .
E 1,2,3 . 1
;
data want;
set have;
array activities
activities_p1-activities_p3
;
array flags(3,4)
flag_p1_1-flag_p1_4
flag_p2_1-flag_p2_4
flag_p3_1-flag_p3_4
;
do i = 1 to dim(activities);
if not missing(activities[i]) then
do j = 1 to hbound(flags,2);
flags (i,j) = sum (flags(i,j), findw(trim(activities[i]),cats(j),',') > 0) > 0;
end;
end;
run;
What's going on ?
flags variables are reset to missing at top of step
hbound return 4 as upper limit of second dimension
findw(trim(activities[i]),cats(j),',') find position of j in csv string
trim needed to remove trailing spaces which are not part of findw word delimiter list
cats converts j number to character representation
findw returns position of j in csv string.
might want to also compress out spaces and other junk if activity data values are not reliable.
first > 0 evaluates position to 0 j not present and 1 present
second > 0 is a another logic evaluation that ensures j present flag remains 0 or 1. Otherwise flags would be a frequency count (imagine activity data 1,1,2,3)
flags(i,j) covers the 3 x 4 slots available for flagging.
Consider converting into a hierarchical view and doing the logic there. The real stickler here is the fact that there can be missing positions within each list. Because of this, a simple do loop will be difficult. A faster way would be multi-step:
Create a template of all possible players and positions
Create an actual list of all players and positions
Merge the template with the actual list and flag all matches
It's not as elegant as a single data step like could be done, but it is somewhat easy to work with.
data have;
infile datalines dlm='|';
input id$ p1_activities$ p2_activities$ p3_activities$;
datalines;
A|1,2,3,4|1,3|
B|1,3|1,2,3|1,2,3|
C| |1,2,3|1,2,3|
D| |1,2,3|
E|1,2,3| |1
;
run;
/* Make a template of all possible players and positions */
data template;
set have;
array players p1_activities--p3_activities;
length varname $15.;
do player = 1 to dim(players);
do activity = 1 to 4;
/* Generate a variable name for later */
varname = cats('p', player, '_act', activity, '_flg');
output;
end;
end;
keep ID player activity varname;
run;
/* Create a list of actual players and their positions */
data actual;
set have;
array players p1_activities--p3_activities;
do player = 1 to dim(players);
do i = 1 to countw(players[player], ',');
activity = input(scan(players[player], i, ','), 8.);
/* Do not output missing positions */
if(NOT missing(activity)) then output;
end;
end;
keep ID player activity;
run;
/* Merge the template with actual values and create a flag when an
an id, player, and activity matches with the template
*/
data want_long;
merge template(in=all)
actual(in=act);
by id player activity;
flag_activity = (all=act);
run;
/* Transpose it back to wide */
proc transpose data=want_long
out=want_wide;
id varname;
by id;
var flag_activity;
run;
Following Stu's example, a DS2 DATA step can perform his 'merge' using a hash lookup. The hash lookup depends on creating a data set that maps CSV item lists to flags.
* Create data for hash;
data share_flags(where=(not missing(key)));
length key $7 f1-f4 8;
array k[4] $1 _temporary_;
do f1 = 0 to 1; k[1] = ifc(f1,'1','');
do f2 = 0 to 1; k[2] = ifc(f2,'2','');
do f3 = 0 to 1; k[3] = ifc(f3,'3','');
do f4 = 0 to 1; k[4] = ifc(f4,'4','');
key = catx(',', of k[*]);
output;
end;end;end;end;
run;
proc ds2;
data want2 / overwrite=yes;
declare char(20) id;
vararray char(7) pact[*] activities_p1-activities_p3;
vararray double fp1[*] flag_p1_1-flag_p1_4;
vararray double fp2[*] flag_p2_1-flag_p2_4;
vararray double fp3[*] flag_p3_1-flag_p3_4;
declare char(1) sentinel;
keep id--sentinel;
drop sentinel;
declare char(7) key;
vararray double flags[*] f1-f4;
declare package hash shares([key],[f1-f4],4,'share_flags'); %* load lookup data;
method run();
declare int rc;
set have;
rc = shares.find([activities_p1],[flag_p1:]); %* find() will fill-in the flag variables;
rc = shares.find([activities_p2],[flag_p2:]);
rc = shares.find([activities_p3],[flag_p3:]);
end;
enddata;
run;
quit;
%let syslast = want2;
share_flags
result

How to do SUM on array from outside file?

I'm newbie college student for programming studies,
so recently i have task to calculate matrix from outside files for Gauss Jordan Numeric Method, in the txt file i provide has 10 (x) and (y) data, and declare with do functions to calculate the 10 data from the txt file each for x^2, x^3, x^4, xy, x^2y
my question is : how to SUM (calculate total) each x^2, x^3 ... that was calculated by program ? i try do sum file in below and still got errors (the first argument of sum must not a scalar.)
the Fortran apps i use was Plato cc from Silverfrost.
I apologize if my english bad and my pogram looks funny.
i have 10 data in my txt looks like these :
(x) (y)
12 10
5 6
28 8
9 11
20 17
6 24
32 9
2 7
1 30
26 22
in program below i open these files and want each x and y i provide read and calculate to get x^2, x^3, x^4, xy, x^2y
Program Gauss_Jordan
Real x(10),y(10),xj,yj,xj2,xj3,xj4,xjyj,xj2yj
Open (10, file='Data.txt')
Do j = 1,10
Read(10,*) x(j), y(j)
xj2 = x(j)**2
xj3 = x(j)**3
xj4 = x(j)**4
xjyj = x(j)*y(j)
xj2yj = (x(j)**2)*y(j)
Do k = 1,10
T(xj2) = SUM( xj2, dim=1)
T(xj3) = SUM (xj3, dim=1)
T(xj4) = SUM (xj4, dim=1)
T(xjyj) = SUM (xjyj, dim=1)
T(xj2yj) = SUM (xj2yj, dim=1)
End Do
End Do
Close(10)
End
for T(xj2) I want to get one result scalar result from SUM the all xj^2 that program has been calculated.
Like in excel was expected :
(A) is 1st xj^2 value that has been calculated
.
.
.
until (J) is 10th xj^2 value that has been calculated
sxj^2 = SUM(Xj^2)
SUM (A-J)
The 'sum' intrinsic needs an array argument, which we can compute from the input arrays without using a loop, so your program could be:
Program Gauss_Jordan
Real x(10), y(10), x2(10), x3(10), x4(10), xy(10), x2y(10)
Open(10, file='Data.txt')
Do j = 1, 10
Read (10, *) x(j), y(j)
End Do
Close(10)
x2 = x**2
x3 = x**3
x4 = x**4
xy = x*y
x2y = (x**2)*y
sx2 = SUM(x2)
sx3 = SUM(x3)
sx4 = SUM(x4)
sxy = SUM(xy)
sx2y = SUM(x2y)
End
From what I see I think you are misunderstanding what the SUM intrinsic does. Since your example isn't storing xj2, xj3 etc. in arrays, SUM isn't going to be useful to you. Instead you could declare totals as scalars (as you described you wanted) and simply add the individual xj2 variables in a loop as in the example below.
Also, you should get in the habit of using the implicit none declaration. It will save you from unexpected errors due to spelling mistakes.
Program Gauss_Jordan
implicit none
Real x(10),y(10),xj,yj,xj2,xj3,xj4,xjyj,xj2yj
real :: Txj2,Txj3,Txj4,Txjyj,Txj2yj
integer :: j
Txj2 = 0
Txj3 = 0
Txj4 = 0
Txjyj= 0
Txj2yj= 0
Open (10, file='Data.txt')
Do j = 1,10
Read(10,*) x(j), y(j)
xj2 = x(j)**2
xj3 = x(j)**3
xj4 = x(j)**4
xjyj = x(j)*y(j)
xj2yj = (x(j)**2)*y(j)
Txj2 = Txj2 + xj2
Txj3 = Txj3 + xj3
Txj4 = Txj4 + xj4
Txjyj = Txjyj + xjyj
Txj2yj = Txj2yj + xj2yj
End Do
print *, 'Txj2 = ', Txj2
Close(10)
End
When I ran this I got the output below which is what I believe you intended:
3175

Assign an array's value as a dimension to another array in SAS

I've been working on a complicated code and am stuck in the end, where I need to assign one array's value as a dimension parameter to another array in the code. A snapshot from my code :
For example:
array temp_match_fl(3) temp_match_fl1 - temp_match_fl3;
ARRAY buracc_repay(3) buracc_repay1 - buracc_repay3;
ARRAY ocs_repay(3) ocs_repay1 - ocs_repay3;
jj = 0;
do until (jj>=3);
jj=jj+1;
If length(strip(match_flag(jj))) = 1 then do;
temp_match_fl(jj) = match_flag(jj);
end;
Else If length(strip(match_flag(jj))) > 1 then do;
j1 = 0;
min_diff = 99999999;
do until (j1>=length(strip(match_class(jj))));
j1=j1+1;
retain min_diff;
n=substr(strip(match_flag(jj)),j1,1);
If (min_diff > abs(buracc_repay(jj)-ocs_repay(n))) then do;
min_diff = abs(buracc_repay(jj)-ocs_repay(n));
temp_match_fl(jj) = n;
end;
end;
end;
kk=temp_match_fl(jj);
/* buracc_repay(jj) = ocs_repay(kk);*/
buracc_repay(jj) = ocs_repay(temp_match_fl(jj));
end;
run;
Now, I need to be able to assign the value stored in temp_match_fl(jj) array as dimension parameter to another array, how can I achieve that?? None of the last two statements work:
buracc_repay(jj) = ocs_repay(kk);
buracc_repay(jj) = ocs_repay(temp_match_fl(jj));
Can someone please suggest.
Thanks!
Actually your last two statements as written do work. Are you getting an error, or unexpected results? Can you make a simple example like below that shows the problem?
Note that for this to work, it's essential that the value of temp_match_fl(jj) is 1, 2, or 3, because your OCS_REPAY array has three elements. From the code you've shown, it's not clear if that is always true. You don't show the match_flag array.
data want ;
array temp_match_fl(3) temp_match_fl1 - temp_match_fl3 (1 2 3) ;
array buracc_repay(3) buracc_repay1 - buracc_repay3 (10 20 30) ;
array ocs_repay(3) ocs_repay1 - ocs_repay3 (100 200 300) ;
jj=1 ;
kk=2 ;
*buracc_repay(jj) = ocs_repay(kk); *this works ;
put temp_match_fl(jj)= ; *debug to confirm value is 1 2 or 3 ;
buracc_repay(jj) = ocs_repay(temp_match_fl(jj)); *this also works;
put (buracc_repay:)(=) temp_match_fl1=; *check output ;
run ;

Porting codes from MATLAB to C(OpenCV)

I've been working on trying to port a small meanshift tracking program, which is sort of different from the meanshift that involves performing back-projection, from MATLAB to C, but I'm having some problems with it.
I don't know how to interpret some of the lines from MATLAB to C(OpenCV).
https://drive.google.com/drive/folders/0B2r9FmkcbNwAbHdtVEVkSW1SQW8
I put the 2 .m files, 1 .cpp file and a directory where pictures are placed for both programs to use on my googledrive.
"demo_MultiMeanShift_1st_ver_0413.m" is what I'd like to port to C,
"boxfilter.m" is the function that's found in the following website:
http://blog.csdn.net/wds555/article/details/23176313
(It's a Chinese website however)
and "Meanshift_demo.cpp" is what I've done so far.
There're mainly two parts that I don't know how to interpret from MATLAB to C:
1st part:
bas = zeros(hei,wid,N) ;
for i = 1 : 1 : N
bas(:,:,i) = boxfilter( ones(hei,wid), floor(r/i) ) ;
end
Ic_mean = zeros(hei,wid,dep,N) ;
for i = 1 : 1 : N
for d = 1 : 1 : dep
%Average pixel value(s) of the object being tracked
Ic_mean(pc(2)-(r+sw) : pc(2)+(r+sw), pc(1)-(r+sw) : pc(1)+(r+sw), d, i) = boxfilter(Ip(pc(2)-(r+sw) : pc(2)+(r+sw), pc(1)-(r+sw) : pc(1)+(r+sw),d), floor(r/i)) ./ bas(pc(2)-(r+sw) : pc(2)+(r+sw), pc(1)-(r+sw) : pc(1)+(r+sw),i);
%Ic_mean(:,:,d,i) = boxfilter(Ip(:,:,d), floor(r/i)) ./ bas(:,:,i);
end
end
dis = zeros(1,N) ;
2nd part:
for i = -sw + pc(2) : 2 : sw + pc(2)
for j = -sw + pc(1) : 2 : sw + pc(1)
for d = 1 : 1 : N
dis(d) = sqrt( ... % (p1(R1, G1, B1) - p2(R2, G2, B2))^2
( Ic_mean(i,j,1,d) - Ip_mean(pc(2),pc(1),1,d) )^2 ...
+ ( Ic_mean(i,j,2,d) - Ip_mean(pc(2),pc(1),2,d) )^2 ...
+ ( Ic_mean(i,j,3,d) - Ip_mean(pc(2),pc(1),3,d) )^2 );
end
if disMin > mean(dis)
disMin = mean(dis) ;
i_hold = i ;
j_hold = j ;
end
end
end
In MATLAB I can read, access and change pixel values directly, such as:
Img(x,y) = 0 to set some pixel value to be 0
or
Img(:,:,1) = 1 to set the pixels of certain channel to all be 0.
Can I also do those things as rapidly as what's shown above is in OpenCV?
In MATLAB I can read, access and change pixel values directly, such
as:
Img(x,y) = 0 to set some pixel value to be 0 or Img(:,:,1) = 1 to set
the pixels of certain channel to all be 0.
Can I also do those things as rapidly as what's shown above is in
OpenCV?
Of course this is possible. To set value of single pixel use:
img.at<img_single_element_type>(y,x) = 0;
where img_single_element_type depends on mat type and might be double, unsigned char, int, etc... See documentation for more information.
To set values in whole image (or part of image) use setTo method.
I don't know much about Matlab, so i can't help you with porting this code, but look at this and this project. It's similar project (object tracker - Open TLD(Tracking Learning Detection) aka Predator) written in Matlab(first link) and ported to C++(second link). Hope it helps.

How do I make this specific code run faster in Matlab?

I have an array with a set of chronological serial numbers and another source array with random serial numbers associated with a numeric value. The code creates a new cell array in MATLAB with the perfectly chronological serial numbers in one column and in the next column it inserts the associated numeric value if the serial numbers match in both original source arrays. If they don't the code simply copies the previous associated value until there is a new match.
j = 1;
A = {random{1:end,1}};
B = cell2mat(A);
value = random{1,2};
data = cell(length(serial), 1);
data(:,1) = serial(:,1);
h = waitbar(0,'Please Wait...');
steps = length(serial);
for k = 1:length(serial)
[row1, col1, vec1] = find(B == serial{k,1});
tf1 = isempty(vec1);
if (tf1 == 0)
prices = random{col1,2};
data(j,2) = num2cell(value);
j = j + 1;
else
data(j,2) = num2cell(value);
j = j + 1;
end
waitbar(k/steps,h,['Please Wait... ' num2str(k/steps*100) ' %'])
end
close(h);
Right now, the run-time for the code is approximately 4 hours. I would like to make this code run faster. Please suggest any methods to do so.
UPDATE
source input (serial)
1
2
3
4
5
6
7
source input (random)
1 100
2 105
4 106
7 107
desired output (data)
SR No Value
1 100
2 105
3 105
4 106
5 106
6 106
7 107
Firstly, run the MATLAB profiler (see 'doc profile') and see where the bulk of the execution time is occuring.
Secondly, don't update the waitbar on every iteration> Particularly if serial contains a large (> 100) number of elements.
Do something like:
if (mod(k, 100)==0) % update on every 100th iteration
waitbar(k/steps,h,['Please Wait... ' num2str(k/steps*100) ' %'])
end
Some points:
Firstly it would help a lot if you gave us some sample input and output data.
Why do you initialize data as one column and then fill it's second in the loop? Rather initialize it as 2 columns upfront: data = cell(length(serial), 2);
Is j ever different from k, they look identical to me and you could just drop both the j = j + 1 lines.
tf1 = isempty(vec1); if (tf1 == 0)... is the same as the single line: if (!isempty(vec1)) or even better if(isempty(vec1)) and then swap the code from your else and your if.
But I think you can probably find a fast vecotrized solution if you provide some (short) sample input and output data.

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