Create sun path chart:


    SRML donation webpage   (Hosted by the University of Oregon)


This program creates sun path charts in either Cartesian or polar coordinates.
A sundial shadow option is also availble.

Three charts types are availble.
1). Standard: An an entire year on the 21st of the month.
2). Single date: A single date specified by the user.
3). Custom date range: A range of dates, with the number of sun paths specified by the user.

All chart types require latitude and longitude coordinates.

Users can select either Cartesian or polar chart types.

Specify location

Latitude:     North is positive.
Range: (-90 to +90) (decimal degrees)

Longitude:   East is positive.
Range: (-180 to +180) (decimal degrees)

  North is AZM = 0 (typical for Northern hemisphere)
  South is AZM = 0 (typical for Southern hemisphere)

Time zone offset in minutes east of UTC. (East is positive.)
    (optional)
If left blank, the time zone offset will be determined using the latitude and longitude. If filled in, the user supplied value will be used.
Example: Pacific time zone is -8.
time zone offset = (-8 * 60) = -480
NOTE: The automatic time zones finder will not work for time zones with non-integer values (ex. Newfoundland -3.5, India +5.5, Nepal +5.75)
For these time zones, the user should explicitly give the time zone offset in the field above. (-3.5* 60 = -210)


Specify date range

Option 1.

Plot all months       Sample image
                      This will plot all months on the 21st of each month.

Option 2.

Plot specific day           Sample image


Year       Month     Day 




This will plot a single date.

Option 3.

Plot custom date range         Sample image

Start date:
Year       Month     Day 


End date:


Number of lines:      
Evenly distrubute the
number of lines
between the start
and end dates.


Specify plot type

Cartesian sun path chart  (x-axis: azimuthal angle, y-axis: elevation angle) 

Polar sun path chart   (Radial direction: SZA, Angular direction: AZM 

Sun dial chart    (x-axis shadow East/West, y-axis: shadow North/South)
Object height:  (Arbitrary units)


NOTE: At least one of these must be checked to see data

Additional parameters


Minute resolution

Time interval between data points. (in minutes)    
One point an hour will plot faster but will not have as much detail
One point every minute will plot slower but will have more detail


Plot contour lines

NOTE: At least one of the countours must be checked to see data

Plot daily countours   
Label format:  YYYY-MM-DD  MMM-DD  No label 

Plot hourly countours   
Label format example  HH:MM  HH   No label 


Plot axis limits

Azimuthal Minimum (degrees):
Azimuthal Maximum (degrees):

Elevation Minimum (degrees): If blank, data limited to (ELV > 0)
Elevation Maximum (degrees):
NOTE: To see all data, set elevation limits to -90, +90.
If axis limits are leftt blank, data will be autoscaled accordingly.


Image resolution

Lower dpi plots faster but does not look as good.
Higher dpi plots slower but has more resolution.
Default: 200