why leading zeros are gets disappeared when i convert an character array to double matrix and can i convert the character array to binary matrix if yes then plz. suggest?

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aditya kumar sahu 2016-11-10

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评论： John D'Errico 2016-11-10

g=str2num(c); c is character array. why leading zeros are gets disappeared when i convert an character array to double matrix and can i convert the character array to binary matrix if yes then plz. suggest..

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aditya kumar sahu 2016-11-10

在 MATLAB Online 中打开

 a=imread('f.jpg');
c=dec2bin(b); /*here c is a character array*\
d=num2cell(c);/*here d is a cell array*\
g=str2num(c);/*here g is a double array*\
we can see in g the binary values leading zeros are eliminated.this is my first doubt
again can i convert the character array 'c' to binary matrix.

Thank you

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Answer 1

Guillaume 2016-11-10

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Because the numbers 001, 01, 1 are all the same (and so is 1 with an infinite numbers of leading 0), numbers are printed without leading zeros. It's the same way we normally write numbers.

Note that matlab has no concept of a binary number. For matlab the number 1001, is the decimal integer between 1000 and 1002, not the equivalent of decimal 9.

As I said before there are matlab functions to manipulate bits of numbers without having to convert them to string or decimal numbers posing as binary.

Also be aware that str2num is a very dangerous function, str2double is much safer. str2num will not just convert strings to numbers, it will also execute any instruction in the string (e.g. format the hard drive).