Use of erf(x); read text file; command to display available functions

Harald Geyer escribi?:
>> It would be good to make plotting work with any data type in
>> Maxima. 
>>     
>
> I don't think there is a canonical meaning of plotting a matrix.
> I'm not sure what you are proposing.
>   

Hello,

These are some interpretations:

a) two-column and two-row matrices: consider paired numbers as point 
coordinates and plot them.
b) one-column and one-row matrices: consider numbers as y values and 
assign abscissas automatically from 1 to n, then plot the pairs.
c) three-column and three-row matrices: as in a), but in 3d.
d) arbitrary dimension matrix: consider m[i,j] as the pixel value of an 
image and render it. These values can be interpreted as gray levels or 
as entries in a color palette.


Present state in Maxima:

a) and c): dataplot in package descriptive should do the job. (I have 
not checked this function for a long time.)
a), b): as Richard suggested, with some pre-processing, both plot2d and 
draw2d could be used.
c): with some pre-processing, you can make use of draw3d.
d): this is already implemented by the image object of the draw package.


Next Maxima release:

All four interpretations will be implemented in the draw package. I'll 
commit to cvs the new version in the next days.


---
Mario Rodriguez Riotorto
www.biomates.net