matplotlib-users

[Matplotlib-users] Equation box

[Flavio C. C. <fcc...@ci...>]

Hi john ,

I was doing a pure TeX plot (a bunch of equations inside a box)  and I 
noticed that the \sqrt{}command does not work even though it listed in 
the help page for mathtext.

\frac and \dfrac would be a nice addition too...

feel free to used this little script as an example of another use of 
mathtext...

Flavio

Re: [Matplotlib-users] Equation box

[John H. <jdh...@ac...>]

>>>>> "Flavio" == Flavio Codeco Coelho <fcc...@ci...> writes:

Hi Flavio,

On an unrelated note, you will be happy to know that wxagg will be
included in the next release, probably early next week.  It's
currently in CVS if you want to get started right away.  font support
has been thoroughly revised and improved by Paul Barrett, and these
changes are not currently documented, so be don't be surprised if you
get some unexpected font warnings in the CVS version.

    Flavio> Hi john , I was doing a pure TeX plot (a bunch of
    Flavio> equations inside a box) and I noticed that the
    Flavio> \sqrt{}command does not work even though it listed in the
    Flavio> help page for mathtext.

    Flavio> \frac and \dfrac would be a nice addition too...

Agreed.  And I guess asking for &=& array layout will be coming soon
:-)

    Flavio> feel free to used this little script as an example of
    Flavio> another use of mathtext...

I will - they look nice!  If you add more to it, be sure to send me
the updated version.

John Gill has written a Cell class for his Table class which is
basically a rectangular box with a text instance inside.  It might be
nice to generalize that code to allow multiple lines of text to be
added

  cell.add_line(t1)
  cell.add_line(t2)

Cell already handles autosizing of the box to surround the text, and
you wouldn't have to mess with turning off the ticks, etc....  John
might be willing to do this, and it could be wrapped in a nice
interface command textbox.

    Flavio> Flavio """ This script create a box with a series of
    Flavio> equations

Your code revealed one bug unrelated to the sqrt problem you
described, but you need to make the change below to have your example
render properly.  In mathtext.py, in the function math_parse_s, change

    maxoy = max(oys)

to 
    maxoy = abs(max(oys))

Now on to your script.  A couple of minor comments first

  text(1,9,r'$dx/dt = \alpha y^{2}$', fontsize=15)
  
the brackets for superscripts are not required; eg, the following is
ok

  text(1,9,r'$dx/dt = \alpha y^2$', fontsize=15)

Normally math functions like sin, cos, exp are in roman type, so I
would use

  text(1,7,r'$dz/dt = \gamma x^2+\rm{sin}(2\pi y+\phi)$', fontsize=15)


As for sqrt, the mathtext syntax differs from TeX.  The main reason is
that I don't draw an overbar with the sqrt symbol group, though this
is something I can add (probably when I get around to dealing with
frac, etc, all of which require some additional drawing and layout).
The point is, you can't use the curly brackets with sqrt or you get a
(silent) parse error.  I'll try and amend the parser to allow the
group.

In the meantime, just do

  text(1,5,r'$\phi = zy +  \Sqrt\alpha\beta $', fontsize=15)

I noticed there is a small clipping bug with sqrt.  There are still
some hacks in the way I layout the cmex fonts which are discussed in
the mathtext documentation - the clipping problem likely arises from
this hack.

Also, note that spaces are respected in font mode, so a hackish way to
include them is \rm{ }.  I've put adding the TeX small space command
\/ on the (growing at an alarming rate) TODO list.  So if you want a
space after zy, you can do

  text(1,5,r'$\phi = zy\rm{ } +  \sqrt\alpha\beta $', fontsize=15)

That's it; here is the modified script that looks great!

from matplotlib.matlab import *
figure(1, figsize=(5,5), dpi=100)
subplot(111)
plot([0])

a=axis([0,10,0,10])
title('Equation Box')
set(gca(),'xticklabels',[])
set(gca(),'yticklabels',[])
set(gca(),'xticks',[])
set(gca(),'yticks',[])

text(1,9,r'$dx/dt = \alpha y^2$', fontsize=15)
text(1,8,r'$dy/dt = \beta x^2$', fontsize=15)
text(1,7,r'$dz/dt = \gamma x^2+\rm{sin}(2\pi y+\phi)$', fontsize=15)
text(1,5,r'$\phi = zy\rm{ } +  \sqrt\alpha\beta $', fontsize=15)


show()

Re: [Matplotlib-users] Equation box

[John N S G. <jn...@eu...>]

 

> I will - they look nice!  If you add more to it, be sure to send me
> the updated version.
> 
> John Gill has written a Cell class for his Table class which is
> basically a rectangular box with a text instance inside.  It might be
> nice to generalize that code to allow multiple lines of text to be
> added
> 
>   cell.add_line(t1)
>   cell.add_line(t2)
> 
> Cell already handles autosizing of the box to surround the text, and
> you wouldn't have to mess with turning off the ticks, etc....  John
> might be willing to do this, and it could be wrapped in a nice
> interface command textbox.

 
I will take a look at this when i get some time.

It might be a week or two though -- i do this stuff commuting on the
train, but unfortunately my laptop recently had a hard drive failure, so
I'm out of action for a while.

Looking forward to getting the latest matplotlib stuff up and running
and trying out all this Agg stuff.

John

Re: [Matplotlib-users] Equation box

[Flavio C. C. <fcc...@ci...>]

Hi John,


On Wed, 2004-04-07 at 13:16, John Hunter wrote:

> >>>>> "Flavio" == Flavio Codeco Coelho <fcc...@ci...> writes:
> 
> Hi Flavio,
> 
> On an unrelated note, you will be happy to know that wxagg will be
> included in the next release, probably early next week. 


That's  great news! I really need to include that equation box in my wx
app. 



> 
>     Flavio> \frac and \dfrac would be a nice addition too...
> 
> Agreed.  And I guess asking for &=& array layout will be coming soon
> :-)


That would be great too!!


> I will - they look nice!  If you add more to it, be sure to send me
> the updated version.


I surely will since this was just a simple draft, to see if it worked. 

> 
> John Gill has written a Cell class for his Table class which is
> basically a rectangular box with a text instance inside.  It might be
> nice to generalize that code to allow multiple lines of text to be
> added
> 
>   cell.add_line(t1)
>   cell.add_line(t2)
> 
> Cell already handles autosizing of the box to surround the text, and
> you wouldn't have to mess with turning off the ticks, etc....  John
> might be willing to do this, and it could be wrapped in a nice
> interface command textbox.


Is this code already in  the 0.52 release? if So, I'll take a look at
it!

> 
>     Flavio> Flavio """ This script create a box with a series of
>     Flavio> equations
> 
> Your code revealed one bug unrelated to the sqrt problem you
> described, but you need to make the change below to have your example
> render properly.  In mathtext.py, in the function math_parse_s, change
> 
>     maxoy = max(oys)
> 
> to 
>     maxoy = abs(max(oys))
> 
> Now on to your script.  A couple of minor comments first
> 
>   text(1,9,r'$dx/dt = \alpha y^{2}$', fontsize=15)
>   
> the brackets for superscripts are not required; eg, the following is
> ok
> 
>   text(1,9,r'$dx/dt = \alpha y^2$', fontsize=15)


In TeX, the curly brackets are necessary when you want more than one
character in the subscript or subscript. That's why I had them there
since I was, at first tryin to do a more complex example.


> 
> Normally math functions like sin, cos, exp are in roman type, so I
> would use
> 
>   text(1,7,r'$dz/dt = \gamma x^2+\rm{sin}(2\pi y+\phi)$', fontsize=15)
> 
> 

You are right, thanks.


> As for sqrt, the mathtext syntax differs from TeX.  The main reason is
> that I don't draw an overbar with the sqrt symbol group, though this
> is something I can add (probably when I get around to dealing with
> frac, etc, all of which require some additional drawing and layout).
> The point is, you can't use the curly brackets with sqrt or you get a
> (silent) parse error.  I'll try and amend the parser to allow the
> group.


That would be a nice idea not to move away from standard TeX syntax...

> 
> In the meantime, just do
> 
>   text(1,5,r'$\phi = zy +  \Sqrt\alpha\beta $', fontsize=15)
> 
> I noticed there is a small clipping bug with sqrt.  There are still
> some hacks in the way I layout the cmex fonts which are discussed in
> the mathtext documentation - the clipping problem likely arises from
> this hack.
> 
> Also, note that spaces are respected in font mode, so a hackish way to
> include them is \rm{ }.  I've put adding the TeX small space command
> \/ on the (growing at an alarming rate) TODO list.  So if you want a
> space after zy, you can do


Ok, TeX has a whole range of space commands that are import to tweak the
layout of math expressions. 

Does mathtext support formatting multiline strings? waht about TeX's
line break command '\\'?

> 
>   text(1,5,r'$\phi = zy\rm{ } +  \sqrt\alpha\beta $', fontsize=15)
> 
> That's it; here is the modified script that looks great!


Thanks again John, mathtext is a great piece of software, and a life
saver for people like me that need to include math symbols in their 
software. I wish I could use it on other parts of my GUI such as menus,
window titles and etc.  

> 
> from matplotlib.matlab import *
> figure(1, figsize=(5,5), dpi=100)
> subplot(111)
> plot([0])
> 
> a=axis([0,10,0,10])
> title('Equation Box')
> set(gca(),'xticklabels',[])
> set(gca(),'yticklabels',[])
> set(gca(),'xticks',[])
> set(gca(),'yticks',[])
> 
> text(1,9,r'$dx/dt = \alpha y^2$', fontsize=15)
> text(1,8,r'$dy/dt = \beta x^2$', fontsize=15)
> text(1,7,r'$dz/dt = \gamma x^2+\rm{sin}(2\pi y+\phi)$', fontsize=15)
> text(1,5,r'$\phi = zy\rm{ } +  \sqrt\alpha\beta $', fontsize=15)
> 
> 
> show()
> 

Re: [Matplotlib-users] Equation box

[John H. <jdh...@ac...>]

>>>>> "Flavio" == Flavio Codeco Coelho <fcc...@ci...> writes:
    Flavio> Is this code already in the 0.52 release? if So, I'll take
    Flavio> a look at it!

No, it doesn't exist yet; it's just an idea that John Gill may want to
pursue.

    Flavio> That would be a nice idea not to move away from standard
    Flavio> TeX syntax...

Agreed.

    Flavio> Ok, TeX has a whole range of space commands that are
    Flavio> import to tweak the layout of math expressions.

    Flavio> Does mathtext support formatting multiline strings? waht
    Flavio> about TeX's line break command '\\'?

None of the above, but I'll try and get some of them in when the more
pressing concerns (fixing the known layout bugs, porting to PS,
improving the parser to handle nested subscripts) are taken care of.

    Flavio> Thanks again John, mathtext is a great piece of software,
    Flavio> and a life saver for people like me that need to include
    Flavio> math symbols in their software. I wish I could use it on
    Flavio> other parts of my GUI such as menus, window titles and
    Flavio> etc.

Well, if wx supports drawing to any of these from freetype fonts or
bitmapped rasters, you probably can.  I can help you with this if the
basic support is in wx.

JDH