intensity_enhance¶
- sunkit_image.radial.intensity_enhance(smap, radial_bin_edges, scale=None, summarize_bin_edges='center', summary=<function mean>, degree=1, normalization_radius=<Quantity 1. solRad>, fit_range=<Quantity [1., 1.5] solRad>, **summary_kwargs)[source]¶
Returns a SunPy Map with the intensity enhanced above a given radius.
The enhancement is calculated as follows:
A summary statistic of the radial dependence of the offlimb emission is calculated. Since the UV and EUV emission intensity drops of quickly off the solar limb, it makes sense to fit the log of the intensity statistic using some appropriate function. The function we use here is a polynomial. To calculate the enhancement, the fitted function is normalized to its value at the normalization radius from the center of the Sun (a sensible choice is the solar radius). The offlimb emission is then divided by this normalized function.
Note
After applying the filter, current plot settings such as the image normalization may have to be changed in order to obtain a good-looking plot.
- Parameters:
smap (
sunpy.map.Map
) – The SunPy map to enchance.radial_bin_edges (
astropy.units.Quantity
) – A two-dimensional array of bin edges of size[2, nbins]
wherenbins
is the number of bins.scale (
astropy.units.Quantity
, optional) – The radius of the Sun expressed in map units. For example, in typical Helioprojective Cartesian maps the solar radius is expressed in units of arcseconds. Defaults to None, which means that the map scale is used.summarize_bin_edges (
str
, optional) – How to summarize the bin edges. Defaults to “center”.summary (
function
, optional) – A function that returns a summary statistic of the radial intensity. Defaults tonumpy.mean
.degree (
int
, optional) – Degree of the polynomial fit to the log of the intensity as a function of radius. Defaults to 1.normalization_radius (
astropy.units.Quantity
, optional) – The radius at which the enhancement has value 1. For most cases the value of the enhancement will increase as a function of radius. Defaults to 1 solar radii.fit_range (
astropy.units.Quantity
, optional) – Array-like with 2 elements defining the range of radii over which the polynomial function is fit. The preferred units are solar radii. Defaults to[1, 1.5]
solar radii.summary_kwargs (
dict
, optional) – Keywords applicable to the summary function.
- Returns:
sunpy.map.Map
– A SunPy map that has the emission above the normalization radius enhanced.