# Plot resolution of axes

Hi all,

I am working on a correlation chart with pyplot for a monitoring web tool. The plot is looking good, but only the strange resolution of axes disturbs the view.

In a simple correlation plot, e.g. I want to compare two temperature sensors, I expect a line who divides the picture in two halves with an angle of 45� (optimal correlation R�=1). That feels natural and you can see whether the both sensors correlate or not without a deeper look at the exact values. But pyplot shows me a chart, where the x-axis's tick interval is larger (108 pixel) than the y-axis's tick interval (77 pixel). In attachment you can see my example.

How can I manipulate the axes that they show the same pixel resolution?

Thank you very much in advance!

Miriam D. Did you try:

ax.set_aspect(‘equal’)

I don’t know how you plotted your figure, so I don’t know which matplotlib objects you have at your disposal. My above example would operate on the Axes object returned by a call to add_subplot() or plt.subplot().

Cheers!
Ben Root

···

On Mon, Mar 25, 2013 at 11:06 AM, Miriam Degginger <md@…4321…> wrote:

Hi all,

I am working on a correlation chart with pyplot for a monitoring web tool. The plot is looking good, but only the strange resolution of axes disturbs the view.

In a simple correlation plot, e.g. I want to compare two temperature sensors, I expect a line who divides the picture in two halves with an angle of 45° (optimal correlation R²=1). That feels natural and you can see whether the both sensors correlate or not without a deeper look at the exact values. But pyplot shows me a chart, where the x-axis’s tick interval is larger (108 pixel) than the y-axis’s tick interval (77 pixel). In attachment you can see my example.

How can I manipulate the axes that they show the same pixel resolution?

Thank you very much in advance!

Miriam D.

Hi Miriam,

This case is a simple one for setting the axis ratios. You want to set
the aspect ratio to equal:
gca().set_aspect('equal')

Jon

···

On Mon, 2013-03-25 at 16:06 +0100, Miriam Degginger wrote:

Hi all,

I am working on a correlation chart with pyplot for a monitoring web
tool. The plot is looking good, but only the strange resolution of axes
disturbs the view.

In a simple correlation plot, e.g. I want to compare two temperature
sensors, I expect a line who divides the picture in two halves with an
angle of 45° (optimal correlation R²=1). That feels natural and you can
see whether the both sensors correlate or not without a deeper look at
the exact values. But pyplot shows me a chart, where the x-axis's tick
interval is larger (108 pixel) than the y-axis's tick interval (77
pixel). In attachment you can see my example.

How can I manipulate the axes that they show the same pixel resolution?

Thank you very much in advance!

Miriam D.

--
______________________________________________________________
Jonathan D. Slavin Harvard-Smithsonian CfA
jslavin@...1081... 60 Garden Street, MS 83
phone: (617) 496-7981 Cambridge, MA 02138-1516
cell: (781) 363-0035 USA
______________________________________________________________

Hi Jon,

yes, this is what I am looking for. Now, the chart is like I've expected.

Thank you all! (...also for the quick response!)

Miriam D.

···

On 25/03/13 17:00, Jonathan Slavin wrote:

Hi Miriam,

This case is a simple one for setting the axis ratios. You want to set
the aspect ratio to equal:
gca().set_aspect('equal')

Jon

On Mon, 2013-03-25 at 16:06 +0100, Miriam Degginger wrote:

Hi all,

I am working on a correlation chart with pyplot for a monitoring web
tool. The plot is looking good, but only the strange resolution of axes
disturbs the view.

In a simple correlation plot, e.g. I want to compare two temperature
sensors, I expect a line who divides the picture in two halves with an
angle of 45° (optimal correlation R²=1). That feels natural and you can
see whether the both sensors correlate or not without a deeper look at
the exact values. But pyplot shows me a chart, where the x-axis's tick
interval is larger (108 pixel) than the y-axis's tick interval (77
pixel). In attachment you can see my example.

How can I manipulate the axes that they show the same pixel resolution?