I would like to write the system of "n" linear equations. Follow is my code:


\systeme*{w_1^S(\delta)=\alpha_1w_{11} + \alpha_2w_{21} + ...+ \alpha_nw_{n1}, w_2^S(\delta)=\alpha_1w_{12} + \alpha_2w_{22} + ...+ \alpha_nw_{n2}, x =...,w_3^S(\delta)=\alpha_1w_{1n} + \alpha_2w_{2n} + ...+ \alpha_nw_{nn}}


Actual Result

However, the actual result is not as what i expect (see below image). I would like to display a "........" in the linear system to demonstrate that my index is keep increasing from i -> n. And at the end, the last equation should display index w_n^S(\delta)= instead of w_3^S(\delta)=. Unfortunately, when I write w_n^S(\delta)= LaTeX recognizes it is not number and it considers it as error Missing = inserted for \ifnum. Also, there is problem if I made "........" in my code. Would you have any ways to work around?

Expected result

  • Do you need \systeme for this? I'm not sure.
    – egreg
    Commented Nov 21, 2015 at 22:11
  • Well, there's a three in your output, because there's a three in the input...
    – jarauh
    Commented Nov 21, 2015 at 22:25
  • 1
    @cfr: I inserted my entire code. Sorry! Commented Nov 21, 2015 at 22:29
  • @jarauh: I know it is 3 in my input since if i write "w_n^S(\delta)=" Latex recognizes it is not number and considers it as "error" "Missing = inserted for \ifnum". Therefore, I currently kept "3" in my input to see the "draft" result. Commented Nov 21, 2015 at 22:32
  • Thanks for completing your example! Fine to post the output that way, but maybe change it back to n in the code so that what you post reproduces the error. It tends to avoid confusion that way.
    – cfr
    Commented Nov 21, 2015 at 22:34

1 Answer 1


You can do it with systeme, but it's better with cases. A small trick ensures perfect alignment. Compare the two versions below.




  w_1^S(\delta)=\alpha_1w_{\di 11} + \alpha_2w_{\di 21} + \dots + \alpha_nw_{\di n1}\\
  w_2^S(\delta)=\alpha_1w_{\di 12} + \alpha_2w_{\di 22} + \dots + \alpha_nw_{\di n2}\\
  w_n^S(\delta)=\alpha_1w_{\di 1n} + \alpha_2w_{\di 2n} + \dots + \alpha_nw_{\di nn}
  w_1^S(\delta)=\alpha_1w_{11} + \alpha_2w_{21} + \dots + \alpha_nw_{n1},
  w_2^S(\delta)=\alpha_1w_{12} + \alpha_2w_{22} + \dots + \alpha_nw_{n2},
  w_4^S(\delta)=\alpha_1w_{1n} + \alpha_2w_{2n} + \dots + \alpha_nw_{nn}

enter image description here

  • Thanks @egreg alot for your help. I see that \systeme somehows deal with index 3, and 4 and output to "n". As you said, cases is more perfect solution. Commented Nov 21, 2015 at 22:39

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .