# How to convert equations to piecewise form

equations={{2 u,2,1+t,1}=={a c,a b+c,a+b,1},{u,t,0,1}=={c d,c+b d,b+d,1}};
Thread/@equations//TraditionalForm


equations was typed to do some Solve

How to get the following TraditionalForm

I typed(I hate typing directly too much) the following equations by hand to show the result expected.

Saving equations to .tex also could get beautiful appearance.

I'd like the equations become beautiful in Mathematica or Tex( Row/Column seems will not preserve the effect after converting to Tex).

So how to convert equations to (1) or (2) both in Notebook and TeXForm? (1) (2)

as @chris mentioned in the comment, this is one good look, so problem is to convert equations to Piecewise in this way.

f[x_] = Piecewise@{{Sin[x], x < 0}, {x, x >= 0 && x < 1}, {x^2, x >= 1}}

f[x]//TeXForm


\begin{cases} \sin (x) & x<0 \\ x & x\geq 0\land x<1 \\ x^2 & x\geq 1 \end{cases}

• Do you want spaces between symbols? Is that all, or do you see another problems? – Dr. belisarius Jun 1 '13 at 14:55
• @belisarius spaces are times, want or not both ok. In Mathematica should have spaces for a c means a*c – HyperGroups Jun 1 '13 at 15:02
• f[x_] = Piecewise@{{Sin[x], x < 0}, {x, x >= 0 && x < 1}, {x^2, x >= 1}} would take f[x]//TeXForm ? – chris Jun 1 '13 at 19:52
• @chris yes, something like this, but f[x] was not created by Piecewise directly, but from equations – HyperGroups Jun 23 '13 at 1:52

## 1 Answer

I think you may be after this good discussion on curly braces.

There is also a Piecewise command, but you seem to be more interested in typesetting.

You can then use the TeXForm command for conversion. Also consider using the Export command if you're comfortable just using an image in your other document.

• The problem is how to convert the equations to Piecewise form. Not by hand (typesetting)... I hate to typeset too much. – HyperGroups Jun 23 '13 at 5:02