exp-mantissa part alone

x=4096; expx = large_exp(x) disp(expx);
how to get only the first part(mantissa part of the answer alone to find exponential and use it in program

 Accepted Answer

x=4096; expx = large_exp(x); mantissa = expx(1);

6 Comments

x
x on 11 Sep 2011
si i used as u said above for various patch values...of thisexpx =
1.0e+006 *
0.0000 -2.6514
for this eg when i used to return only the mantissa part the answer must b 0 onlu na sir but i get 2.2722 and for most of my calculation i get 0.0000 only but returning some other values sir..what will b the problem
x
x on 11 Sep 2011
si i used as u said above for various patch values...of thisexpx =
1.0e+006 *
0.0000 -2.6514
for this eg when i used to return only the mantissa part the answer must b 0 onlu na sir but i get 2.2722 and for most of my calculation i get 0.0000 only but returning some other values sir..what will b the problem
x
x on 11 Sep 2011
again in my pgm i am in need of calculating exp(5.6458e+007) so when using the functn call which u mentioned yet i get
expx =
1.0e+007 *
0.0000 -2.4519 still zero but NAN get eliminated..and when finding mantissa alone i didn't get 0.000 instead i get 1.3375 ...y this occurs..?because of loop ah?and wt 2 do for that zero occurence
If you read the documentation for the "format" command, matters should become clearer.
x
x on 12 Sep 2011
sir where to use the format?why these mantissa values are different ?where to use format sir
As the first executable line of your program, put
format long g
After that, you will not get those silly 1.0e+007 * displays, and you will be able to see why the mantissa showed up as 1.3375 instead of 0.000 .

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More Answers (1)

the cyclist
the cyclist on 11 Sep 2011

0 votes

I am not sure what you mean by large_exp(). I assume it is a function you wrote, or maybe it is in a toolbox that I do not have. Regardless, I expect that you can get at what you need by using the floor() function.

2 Comments

x
x on 11 Sep 2011
inorder to calculate exp me used a function call and it gives expx =
1.0e+003 *
0.0074 1.7780 as my value for fimdimg exp(4096) the ans is the mantissa part alone ie)i want to get only 1.0e+003 *
0.0074 alone for this wt is to b done
x
x on 11 Sep 2011
function expx = large_exp(x)
t = x/log(10);
expx = [10^(t-floor(t)), floor(t)];
this s the fuction pgm

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