... sin f = y / r . cos f = x / r . ... They are now viewed as new definitions of the sine and cosine, for the polar angle f given by x and y ( a slightly different way of formulating this definition is described further below ). ... sin 2 f + cos 2 f = 1 . ... Angle . ... Many trigonometry texts define the sine and cosine slightly differently, using the so-called unit circle . ... Then the distance AB ("the sine line") equals sin a , and the distance OA ("the cosine line") equals cos a . ...

... In polar coordinates, the point P is defined by its distance r from the origin O (see drawing) and by its polar angle ("azimuth" on a map) between the x-axis and the "radius" r = OA, measured counter-clockwise. ... When one or both are negative , the angle f is larger than 90 degrees, and such angles never appears in any right-angled triangle. ... There is a simple solution , though: use the above equations to re-define sin f and cos f for such larger angles! ... But it also works for larger angles....

... The exact directions of the offsets are parallel to the rows and columns of the CCD on which the aperture is specified. ... It is often useful to explicitly specify the desired rotation of the WFPC2 field-of-view on the sky. ... Figure 7.8 shows the CCD orientation and aperture locations relative to the U3 axis. ... Obtain the Position Angle (PA) of the source axis on the sky, measured in the standard way, North through East. ... desired source angle in field-of-view measured CW from +U3 axis) . ...

lsst.coordConv љ unknown . ... coordConv::Coord Class Reference . ... Coord (double equatAng, double polarAng, double parallax=0) . ... Definition at line 27 of file coord.h . ... Definition at line 227 of file coord.cc . ... Definition at line 150 of file coord.cc . ... Definition at line 134 of file coord.cc . ... Definition at line 142 of file coord.h . ... Definition at line 135 of file coord.h . ... Definition at line 141 of file coord.cc . ... Definition at line 172 of file coord.cc . ...

... The first of the equations defines the position of the spectral orders, m , in the raw image, while the second equation gives, for each order, the dispersion relation in one dimension. ... where the coefficients are computed using least squares techniques on a grid , i.e. sample number and line number of points located within the spectral orders of the image. These points in the grid are found automatically by an order--following algorithm, normally using the FLAT or STD image. ...

... Classes . ... Class List . ... casa . casa::SolarPos . ... Solar position class and calculations. ... SolarPos (const SolarPos &other) . ... operator() ( Double epoch) . ... Barycentric position of Earth. const MVPosition & casa::SolarPos::baryEarthDerivative . ... Barycentric position of Sun. const MVPosition & casa::SolarPos::barySunDerivative . ... Double casa::SolarPos::checkEpoch [private] . ... Double casa::SolarPos::checkSunEpoch [private] . ... Double casa::SolarPos::deval [3] [private] . ...

... The routine returns the offset (deltaX, deltaY) from the linear grid position for a specified detector location. ... the distortion (deltaX, deltaY) at the detector location (rawX, rawY) is derived from the distortion map stored in the extension FILTER-FilterId (e.g. FILTER-U, FILTER-V, FILTER-GRISM1 etc.) ... interpolate the extracted distortion points (RAWX_OFF ,RAWY_OFF ) and calculate the distortion (deltaX,deltaY) at the requested postion (rawX, rawY) . ... deltaX, deltaY . ...

... The HST uses an onboard model of its orbit to perform in real-time various control functions relating to spacecraft operations and observation support. ... New coefficients for the ephemeris are updated every other day, and are archived as FITS keywords for each HST observation data set. Using these coefficients,an observer can perform a variety of calibration and characterization calculations relating to the orbital position and velocity of the telescope. ...

... When feed is rotated over the tertiary: . ... z is toward the tertiary from the focus position . ... angle : Center of rotation is about the optical axis. range 0 to 360 degrees (minus a few degrees for the limits) . ... CW when sitting on the tertiary looking up at the dipoles. radius : moves in the x,y plane along the direction that the angle currently points . ... Dipole positions : . ... D1 is at the center of the dipole array. processing: x101/projects/byuPhAr/idl/doplotoff.pro . ...