Thread: [Matplotlib-users] [matplotlib-users] Using variables in annotations

Hi,
Is it possible to print the value of a variable in an annotation?
Example:
gradient = 2.0
intercept = 3.0
r-value = 0.99
ax.annotate('f(x) = gradient * x + intercept R^2 = r-value',
xy=(2.9,-0.75), xytext=(2.9,-0.75))
Where gradient, intercept and r-value should be replaced by the value
of the variables in the output.
Regards and a happy new year!
Manuel Wittchen

Manuel Wittchen skrev:
> Is it possible to print the value of a variable in an annotation?
> Example:
> 
> gradient = 2.0
> intercept = 3.0
> r-value = 0.99
> 
> ax.annotate('f(x) = gradient * x + intercept R^2 = r-value',
> xy=(2.9,-0.75), xytext=(2.9,-0.75))
> 
I feel that a main advantage of matplotlib (over other solutions I have 
used) is that there is a complete programming language available. In 
this case, just use the standard string handling of python.
See e.g. http://docs.python.org/library/stdtypes.html#string-formatting
Untested code:
annotation_string = "f(x) = %f * x + %f R^2 = %f" % (gradient, 
intercept, r-value)
ax.annotate(annotation_string,
xy=(2.9,-0.75), xytext=(2.9,-0.75))
/ johan