read/load parts of the irregular file by Matlab - matlab

I would like to partly load a PTX file by matlab (please see the following example)
I need to read and write the first two row (2 numbers) into 2 variables say a and b. And read and write the data from 5th row to the end into a matrix
Thanks for your help
114
221
1 0 0
1 0 0 0
-5.566405 -7.161944 -1.144557 0.197208 24 29 35
-5.560656 -7.154540 -1.137673 0.222400 29 32 39
-5.559846 -7.153491 -1.131895 0.254002 37 40 49
-5.560894 -7.154833 -1.126452 0.305013 51 54 63
-5.560084 -7.153783 -1.120633 0.290013 72 76 88
-5.561128 -7.155119 -1.115189 0.243214 105 113 134
-5.563203 -7.157782 -1.109926 0.227604 130 143 177
-5.569191 -7.165479 -1.105504 0.201602 121 140 173
-7.833616 -10.078705 -1.546952 0.130007 94 112 134

Look at the tdfread function in order to get the data into Matlab. It should be something like datafile = tdfread(filename, '\t'). Once you have that, index into the variable returned from that function like
a = datafile(1, 1);
b = datafile(2, 1);
data = datafile(5:end, :);

Related

setxor single value of cell array with whole cell array values?

My cell array,it contain values like
a=['10100011' '11000111' 00010111' 11100011 '];
I want to apply xor operation ;
I used setxor. I want to xor first value of array i.e 10100011 to all values of cell arrays,required input & output is as follows !
**setxor(10100011, 10100011) =00000000%(first value xor result with first value)
setxor(10100011 , 11000111) =1100100%(first val xor result with second value)
setxor(10100011, 00010111 )=10110100%(first val xor result with third value)
setxor(10100011 ,11100011)=1000000 %(first val xor result with forth value)**
but i don't know how to pass full cell array and single value, i tried to use cellfun but that's not working. I want something that setxor(first val of my cell array , all vals of my cell array) as my cell array is 16x16. Your help would be highly appriciated.
If you're starting from data that looks like this:
A = [163 215 9 131 248 72 246 244 179 33 21 120 153 177 175 249; ...
231 45 77 138 206 76 202 46 82 149 217 30 78 56 68 40];
And you want to XOR the bits of the first entry with every other entry, you don't have to convert A using dec2bin. You can just use bitxor, then format the result however you want (decimal or cell arrays of binary strings):
>> decOut = bitxor(A(1), A)
decOut =
0 116 170 32 91 235 85 87 16 130 182 219 58 18 12 90
68 142 238 41 109 239 105 141 241 54 122 189 237 155 231 139
>> binOut = reshape(cellstr(dec2bin(decOut)), size(A))
binOut =
2×16 cell array
Columns 1 through 10
'00000000' '01110100' '10101010' '00100000' '01011011' '11101011' '01010101' '01010111' '00010000' '10000010'
'01000100' '10001110' '11101110' '00101001' '01101101' '11101111' '01101001' '10001101' '11110001' '00110110'
Columns 11 through 16
'10110110' '11011011' '00111010' '00010010' '00001100' '01011010'
'01111010' '10111101' '11101101' '10011011' '11100111' '10001011'

Importing CSV into Matlab

Chemical composition of a certain material
Hi,
I am trying to import the below mentioned data in CSV format in matlab, which is [1000x10] in dimensions.
HCL;H2SO4;CH4; SULPHUR;CHLORINE;S2O3;SO2;NH3;CO2;O2
144 2 3 141 140 6 7 137 136 10 11 133
13 131 130 16 17 127 126 20 21 123 122 24
25 119 118 28 29 115 114 32 33 111 110 36
108 38 39 105 104 42 43 101 100 46 47 97
96 50 51 93 92 54 55 89 88 58 59 85
61 83 82 64 65 79 78 68 69 75 74 72
73 71 70 76 77 67 66 80 81 63 62 84
60 86 87 57 56 90 91 53 52 94 95 49
48 98 99 45 44 102 103 41 40 106 107 37
109 35 34 112 113 31 30 116 117 27 26 120
121 23 22 124 125 19 18 128 129 15 14 132
12 134 135 9 8 138 139 5 4 142 143 1
I am able to import this data through my code
fid = fopen(uigetfile('.csv'),'rt');
FileName = fopen(fid);
headers = fgets(fid); %get first line
headers = textscan(headers,'%s','delimiter',';'); %read first line
format = repmat('%f',1,size(headers{1,1},1)); %count columns n makeformat string
data = textscan(fid,format,'delimiter',';'); %read rest of the file
data = [data{:}];
I am getting data in matrix form in variable data [1000x10] and name of all the components like HCL, H2SO4 in a cell array named headers{1x1}.
Now I have two questions like the built in import feature in matlab you have flexibility to import data as separate column vectors, numeric matrix,cell array and table format. Is it possible to do as such through code, like i get column vectors with their name HCL with [1000x1] and H2sO4 with [1000x1] in my workspace after import and so on all the column vectors with their names with [1000x1]dimensions.
if yes then help me please...?
If above mentioned is not possible then i can do alternatively that now I have names of column vectors in headers cell array, how I can extract those name and use those names as column vector names through code and I can assign data from data matrix [1000x10] to each column vector with their corresponding names.
like if i say
x = headers {1*1}{1*1}; i will get x = "HCL"
x = genvarname(x); I will get x= x0x22HCL0x2 BUT
I want that x get replaced with HCL.and then I assign
HCL = data(:,1) and same like this other variables H2SO4,SULPHUR, CHLORINE.
You can say i try to implement the import feature of column vector through my code.
Kindly help me to solve this issue. thanks
Have you tried the built-in readtable function?
You can access each column of the table by using the named column header.
If you'd like, you can use the two data types to create a table in MatLab. I'm not terribly familiar with its use, but it seems to be well documented. I'm sure someone else can expand upon this.
Edit:
After re-reading your question, I think this is closer to what you are after.
n=10;
what='HCL';%change this to any of the strings you interested in
numstr = repmat('%f',1,n);
hdrstr = repmat('%s',1,n);
headers = textscan(headers,hdrstr,'delimiter',';');
headers = headers(1,:)
data = cell2mat(textscan(fid,numstr,'delimiter',';'));
datout = data(:,strcmp(headers,what));%datout will be 1000x1 HCL data
Depending on what you want to do, you can loop through these appropriately
I know this is not what you asked for, but I would convert to a struct:
x=cell2struct(num2cell(data),headers,2)
reason is simple, selecting for example the third row with individual variables is not possible. With a struct simply use x(3)
If at some point you need the vectors you originally asked for and you can't use the strcut, use [x.HCL]

Matlab .txt file read using space delimiter

I want to read a text file into a matrix using space delimiter.My text file contains information like this:
AJ_Lamas/AJ_Lamas_0001.jpg 58 68 134 134 -2 10 31 43 53 45
Aaron_Eckhart/Aaron_Eckhart_0001.jpg 63 72 126 126 0 10 34 35 53
Aaron_Guiel/Aaron_Guiel_0001.jpg 54 67 144 144 -1 10 34 44 58
Aaron_Patterson/Aaron_Patterson_0001.jpg 47 62 148 148 1 10 44 65 63
Aaron_Peirsol/Aaron_Peirsol_0001.jpg 64 72 127 127 0 10 33 43
I tried :
m=dlmread('D:\MatlabCode\lfw_ffd_ann.txt', ' ')
but it shows some errors:
Error using dlmread (line 139)
Mismatch between file and format string.
Trouble reading number from file (row 1u, field 1u) ==> image_name
face_bbox_x face_bbox_y face_bbox_width face_bbox_height headpose
num_facial_features left_eye_left_x left_eye_left_y left_eye_right_x
left_eye_right_y mouth_left_x mouth_left_y mouth_right
You can't really read it itno a matrix, but into a cell and can achieve it with textscan(). Supposing you want to read the actuall strings (which I assume because of the file names), it would go something like this:
fid=fopen('D:\MatlabCode\lfw_ffd_ann.txt');
C=textscan(fid,'%s','delimiter',' ');
fclose(fid);
hope that helps

MATLAB accessing conditional values and performing operation in single column

Just started MATLAB 2 days ago and I can't figure out a non-loop method (since I read they were slow/inefficient and MATLAB has better alternatives) to perform a simple task.
I have a matrix of 5 columns and 270 rows. What I want to do is:
if the value of an element in column 5 of matrix goodM is below 90, I want to take that element and and subtract it from 90.
So far I tried:
test = goodM(:,5) <= 90;
goodM(test) = 999;
It changes all goodM values within column 1 not 5 into 999, in addition this method doesn't allow me to perform operations on the elements below 90 in column 5. Any elegant solution to doing this?
edit:: goodM(:,5)(test) = 999; doesn't seem to work either so I have no idea to specify the target column.
I am assuming you are looking to operate on elements that have values below 90 as your text in the question reads, rather than 'below or equal to' as represented by '<=' as used in your code. So try this -
ind = find(goodM(:,5) < 90) %// Find indices in column 5 that have values less than 90
goodM(ind,5) = 90 - goodM(ind,5) %// Operate on those elements using indices obtained from previous step
Try this code:
b=90-a(a(:,5)<90,5);
For example:
a =
265 104 479 13 176
26 110 447 208 144
379 163 179 366 464
301 48 274 391 26
429 374 174 184 297
495 375 312 373 82
465 272 399 447 420
205 170 373 122 84
1 417 63 65 252
271 277 412 113 500
then,
b=90-a(a(:,5)<90,5);
b =
64
8
6

Selecting elements of a vector based on two vectors of starting and ending positions matlab

I would appreciate your help with the following problem in matlab:
I have a vector and I would like to select parts of it based on the following two vector of start and end indices of parts:
aa = [1 22 41 64 83 105 127 147 170 190 212 233]
bb = [21 40 63 82 104 126 146 169 189 211 232 252]
Basically I would like to perform some function on V(1:21), V(22:40),... V(233:252).
I have tried V(aa:bb) or V(aa(t):bb(t)) where t = 1:12 but I get only V(1:21), probably because V(22:40) has 19 elements compared to V(1:21) which has 22 elements.
Is there a fast way of programming this?
Put your selection in a cell array, and apply your function to each cell:
aa = [1 22 41 64 83 105 127 147 170 190 212 233]
bb = [21 40 63 82 104 126 146 169 189 211 232 252]
V = rand(252,1); % some sample data
selV = arrayfun(#(t) V(aa(t):bb(t)), 1:12,'uniformoutput',false);
result = cellfun(#yourfunction,selV)
% or
result = cellfun(#(selVi) yourfunction(selVi), selV);
If the function you want to apply has scalar output to every vector input, this should give you an 1x12 array. If the function gives vector output, you'll have to include the uniformoutput parameter:
result = cellfun(#(selVi) yourfunction(selVi), selV,'uniformoutput',false);
which gives you a 1x12 cell array.
If you want to run this in a highly condensed form, you can write (in two lines, for clarity)
aa = [1 22 41 64 83 105 127 147 170 190 212 233]
bb = [21 40 63 82 104 126 146 169 189 211 232 252]
V = rand(252,1); % some sample data borrowed from #Gunther
%# create an anonymous function that accepts start/end of range as input
myFunctionHandle = #(low,high)someFunction(V(low:high));
%# calculate result
%# if "someFunction" returns a scalar, you can drop the 'Uni',false part
%# from arrayfun
result = arrayfun(myFunctionHandle(low,high),aa,bb,'uni',false)
Note that this may run more slowly than an explicit loop at the moment, but arrayfun is likely to be multithreaded in a future release.