From 71cbfa20a3a970b93a22ff7036b29bb2433097bc Mon Sep 17 00:00:00 2001 From: Mattias Andrée Date: Fri, 30 May 2014 20:39:23 +0200 Subject: doc MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Signed-off-by: Mattias Andrée --- info/blueshift.texinfo | 42 ++++++++++++++++++++++++++++++++++-------- 1 file changed, 34 insertions(+), 8 deletions(-) (limited to 'info/blueshift.texinfo') diff --git a/info/blueshift.texinfo b/info/blueshift.texinfo index 86783d0..be30aad 100644 --- a/info/blueshift.texinfo +++ b/info/blueshift.texinfo @@ -1262,12 +1262,12 @@ point. It has three optional, additional, parameters: The time in Julian Centuries. @item low = -6.0 -The Suns elevation at the limit to high night, that +The Sun's elevation at the limit to high night, that is, the highest possible position (measured in degrees) of the Sun before it becomes visible. @item high = 3.0 -The Suns elevation at the limit to high day, that is, +The Sun's elevation at the limit to high day, that is, the lowest possible position (measured in degrees) of the before it starts becoming less visible (twilight.) @end table @@ -1365,12 +1365,42 @@ Calculates the time the Sun has the apparent elevation time the closest the solar noon. @item solar_elevation_from_time(t, latitude, longitude) -Calculates the Suns elevation, in degrees, as apparent from the +Calculates the Sun's elevation, in degrees, as apparent from the geographical position (@code{latitude}, @code{longitude}). @item solar_elevation(latitude, longitude, t = None) Calculates the same thing as @code{solar_elevation_from_time}, except the time is optional and defaults to the current time. + +@item future_past_elevation(delta, latitude, longitude, elevation, t = None) +Calculates the next or previous point in time the Sun's +elevation will be @code{elevation} degrees or was +@code{elevation} degrees at the geographical position +(@code{latitude}, @code{longitude}). The calculated +timepoint may actually be the current time, @code{t}. +If not time point can be found within a Julian year +@code{None} will be returned. This function uses +interpolation to determine time point, because inverting +@code{solar_elevation} is unfeasible to do algebraically; +@code{delta} specified the size of the steps between the +timepoints that are tested to determine the timespan in +which to do the interpolation. + +@item future_elevation(latitude, longitude, elevation, t = None) +Calculates the next point in time the Sun's elevation will +be @code{elevation} degrees at the geographical position +(@code{latitude}, @code{longitude}). The calculated +timepoint may actually be the current time, @code{t}. +If not time point can be found within a Julian year +@code{None} will be returned. This function uses + +@item past_elevation(latitude, longitude, elevation, t = None) +Calculates the previous point in time the Sun's elevation was +@code{elevation} degrees at the geographical position +(@code{latitude}, @code{longitude}). The calculated +timepoint may actually be the current time, @code{t}. +If not time point can be found within a Julian year +@code{None} will be returned. This function uses @end table For all functions beneath @code{degrees}, @code{t} is the @@ -1771,10 +1801,6 @@ questions''. The predefined colour temperatures, in order of warmness, are: -@c XXX can we use a proper kelvin symbol instead -@c of K, that is, K with all three stroked -@c intersecting (the K [U+212A] symbol)? - @table @code @item K_F_LUX_W32_EMBER = 1200 K The colour temperature in the Windows port of f.lux named `ember'. @@ -2273,7 +2299,7 @@ until the user terminates Blueshift. Running Blueshift such at it applies adjustments and than exits. - @item Panicgate +@item Panicgate Applying adjustments immediately without transitioning. This terminology is borrowed from OpenNTPD. -- cgit v1.2.3-70-g09d2