Output truncated. Text exceeds maximum line length of 25,000 characters for Command Window display.

hello

i have tried to find determian of of 7 by 7 matrices with all symbolic entries but it showes

Output truncated. Text exceeds maximum line length of 25,000 characters for Command Window display.

so i have used many expressions but still does not work. who can help me

with respect.

These are my typing

>> syms a12 b12 a13 b13 a14 b14 a15 b15 a16 b16 a23 b23 a24 b24 a25 b25 a26 b26 a34 b34 a35 b35 a36 b36 a45 b45 a46 b46 a56 b56 A B C D E F G a17 a27 a37 a47 a57 a67 b17 b27 b37 b47 b57 b67

>> X=[A a12 a13 a14 a15 a16 a17;b12 B a23 a24 a25 a26 a27;b13 b23 C a34 a35 a36 a37;b14 b24 b34 D a45 a46 a47;b15 b25 b35 b45 E a56 a57;b16 b26 b36 b46 b56 F a67;b17 b27 b37 b47 b57 b67 G]

S=det(X)

Answer 1

[Steven Lord]

Since I'm guessing you don't really want to read through pages and pages of the result of that command, suppress the display by ending the line where you call det with a semicolon.

Alternately, substitute numeric values for some or all of the elements of that matrix before calling det rather than (as I suspect you're planning to do) substituting after.

[wlat hamad]

really i need all terms with symbolic entries, i am not going to substitute any elements by number but i know result consist of 5040 terms. i have used diary comand but it gives me error when i was typied get(0,diary) it does not work why?

you are dont mind if i aked you to run it ? please

This is my e.address: [e-mail]

with best respect

[Steven Lord]

What are you planning to do with those 5040 terms? Why do you need to read the extremely long output of that command?

[wlat hamad]

Those terms tell us many things. Do you guess any way to see them? Please

[Steven Lord]

When I compute the determinant of a generic 7-by-7 matrix:

>> syms x [7 7]
>> S = det(x);
>> strlength(char(S))
ans =
      186477

Using the general rule of thumb of 3000 characters per page, that means this is a sixty-three page long expression.

If you must read this, write char(S) to a text file and open that file.

[wlat hamad]

but it does not work

gives error.

really i am traing do a reserch

[Steven Lord]

Make sure you're in a folder where you have write permissions then run this code:

syms x [7 7]
S = det(x);
writematrix(char(S), 'determinant.txt')
edit determinant.txt

[wlat hamad]

could you run my request please my App does not work well.

i need it please

sorry for annoying you.

[Steven Lord]

Here is the text file.

[Walter Roberson]

Output attached.

"Those terms tell us many things."

No they don't. They are uninformative. They are just a long string of additions that look like

G*a12*a35*a46*b12*b35*b46 + G*a12*a35*a46*b12*b36*b45 + G*a12*a36*a45*b12*b35*b46

[wlat hamad]

well done dear Steven Lord

i appriciate your effort many thanks

[wlat hamad]

Dear Walter Roberson

i have submitted a reserch which related this determinant .

if you wish we can do the same or send me your e-mail i will send you many reserches that depended this case . are you a mathician ??

with best respect

[Walter Roberson]

"A mathematician is a person who does mathematics" -- Raymond M. Smullyan I think it was.

I do not think I have an interest in the wonders of 7 x 7 determinants at this time.

[wlat hamad]

Dear prof Walter Roberson

please see the folowing paper which we used 6 by 6 determinant of a marix

http://www.m-hikari.com/imf/imf-2020/5-8-2020/91282.html

you can do the same of 7 by 7 if you wish . also i can help you ,,,

[Walter Roberson]

@wlat hamad

Thank you, but that is not a topic I have an interest in.

[wlat hamad]

Great dear brother. I have one more problem could you help me? I have found all terms of 7 by 7 detriment of a specific matrix, so i know many results are same or has been repeated, i would like to collect all that terms which are same, although maybe they are not entirely same for example All results are like that a_{12}*a_{34}*a_{45}*a_{24}*b_{12}*b_{34}+.... I know the above equation is being repeated over this 5020 terms but maybe appear like this a_{12}*a_{34}*a_{45}*a_{24}*b_{12}*b_{34}+... = a_{34}*a_{12}*a_{24}*a_{45}*b_{12}*b_{34}+...

Could you solve this? Best regards

[Steven Lord]

You can try using the subexpr function, but I'm not sure how much more readable (if at all) it's going to make this sixty-three page long expression.