problem using num2str and bin2dec in size

having an array of 32*32 when using num2str i get a char array of 32*94 why? i cannot use bin2dec on it

data = uint32(randi(2^31,[32,1]));
m = de2bi((data),32);
groups = num2str(m');

the array groups will be of type char 32*94 i cannot convert it to decimal :S

- - - Updated - - -
tic
data = uint32(randi(2^31,[32,1]));
m = de2bi((data),32);
groups = (m');
power2=[1,32];

for i=1:32
power2(i)=2^(i-1);
end

power2=uint32(power2);
decnum=[1,32];

for i=1:32
decnum(i)=(sum(power2.*groups(i,:)));
end

decnum=uint32(decnum);
toc

this is the updated code but it is somekind of slow if i want to do it on 500 000number any suggestions plz?

Answer 1

[Iman Ansari]

Hi

groups(:,1:3:end) %makeing result 32*32 again

Try this(Your updated code):

data = uint32(randi(2^31,[32,1]));
m = de2bi((data),32);
groups = num2str(m');
a=groups(:,end:-3:1);
b=bin2dec(a);
c=uint32(b);

Answer 2

[ghattas akkad]

thank you how did this do it ?

[Iman Ansari]

See this:

m = de2bi((4),8)
groups = num2str(m)
groups2 = groups(1,1:3:end)

the groups has two space between its numbers.

Answer 3

[ghattas akkad]

there is some problem the result of c in your code after the bin2dec is different then the ones i obtained in the array decnum

[ghattas akkad]

and the matrices groups and a are different

[ghattas akkad]

ok the matrix a needs a mirror

[ghattas akkad]

i dont think that is bcz of the rand function

[Iman Ansari]

No:

clear
%%%%%mine
data = uint32(randi(2^31,[32,1]));
m = de2bi((data),32);
groups1 = num2str(m');
a=groups1(:,end:-3:1);
b=bin2dec(a);
c=uint32(b);

%%%%%%yours
groups = (m');
power2=[1,32];
for i=1:32
power2(i)=2^(i-1);
end
power2=uint32(power2);
decnum=[1,32];
for i=1:32
decnum(i)=(sum(power2.*groups(i,:)));
end
decnum=uint32(decnum);

mineVsyours=[c decnum']

[ghattas akkad]

i think my code has a problem :) thank you :D

Answer 4

[ghattas akkad]

when update the code to look like this clear all close all

tic

data = uint32(randi(2^31,[500000,1]));

m = de2bi((data),32); groups = num2str(m'); a=groups(:,end:-3:1);

b=bin2dec(a); c=uint32(b);

toc

generate 500 000 numbers i get this error

Error using bin2dec (line 36) Binary string must be 52 bits or less.

Error in datatobin2 (line 12) b=bin2dec(a);

why ??

[Iman Ansari]

bin2dec support string with at max 52 width. You want to convert to decimal a binary number with 500000 bits width, then with uint32 convert it back to 32 bits number?

Please explain what you want to do with this code.

[ghattas akkad]

generate 500 000 numbers convert them to binary to group each set of bits together like a group of 1st bits = 1st row group of second bits=second row..... then convert them to decimal and send them to fpga using DMA to my sequential sorter

[Iman Ansari]

500000 is very big but for lower number like 1000:

clear
data = uint32(randi(2^31,[1000,1]));
m = de2bi((data),32);
groups1 = num2str(m');
a=groups1(:,end:-3:1);
b=0;
for i=1:52:size(a,2)
    b=b+bin2dec(a(:,i:min(i+51,end))).*2^(i-1);
end

But I think you shouldn't use c=uint32(b) after this.