format for decimal numbers and no fractional

How i can obtain results in decimal format and not in fractional format?

I am using matlab for direct knematic, for example :

For a matrix I expect the following result: A12 =

[ 0, 0, 1, 0]

[ 1, 0, 0, 0]

[ 0, 1, 0, d2]

[ 0, 0, 0, 1]

but matlab show : A12 =

[0, -4967757600021511/81129638414606681695789005144064, 1, 0]

[ 1, 0, 0, 0]

[ 0, 1,4967757600021511/81129638414606681695789005144064, d2]

[ 0, 0, 0, 1]

where i expect a 0 i have a fractional number 4967757600021511/81129638414606681695789005144064

Answer 1

[the cyclist]

I suggest you read

doc format

for complete info on how MATLAB displays to the command window.

If you mean something else, please add more detail to your question, which is very imprecise.

[Noe alvarado]

I am using matlab for direct knematic, for example :

For a matrix I expect the following result: A12 =

[ 0, 0, 1, 0]

[ 1, 0, 0, 0]

[ 0, 1, 0, d2]

[ 0, 0, 0, 1]

but matlab show : A12 =

[0, -4967757600021511/81129638414606681695789005144064, 1, 0]

[ 1, 0, 0, 0]

[ 0, 1,4967757600021511/81129638414606681695789005144064, d2]

[ 0, 0, 0, 1]

where i expect a 0 i have a fractional number 4967757600021511/81129638414606681695789005144064

[the cyclist]

I'm not sure why you see that. What do you get if you type

get(0,'format')

Does it fix the problem if you type

format short

What class of variable is A12?

[Noe alvarado]

A12 is a homogeneous transformation matrix. the following expresion compute this matrix

[cos(teta) -cos(alfa)*sin(teta) sin(alfa)*sin(teta) a*cos(teta);

sin(teta) cos(alfa)*cos(teta) -sin(alfa)*cos(teta) a*sin(teta);

0 sin(alfa) cos(alfa) d

0 0 0 1];

with teta=pi/2

syms d2

d=d2

a=0

alfa=pi/2

and when a type get(0,'format')

ans =

short

[the cyclist]

I'm not sure what's happening here, and I don't have the Symbolic Math Toolbox, so I can't really test any ideas. I'm guessing that those fractions are the closest representation that MATLAB can get to the actual values, but I don't really know.

[Deepak Ramaswamy]

That is the rational representation of the number as computed by the symbolic math toolbox. convert to float using

double(A12)