### CREFRAME

Generates a test two-dimensional NDF with a selection of several forms

#### Description:

This application creates a two-dimensional output NDF  containing artificial data of various forms (see Parameter MODE). The output NDF can, optionally, have a VARIANCE component describing the noise in the data array (see Parameter VARIANCE), and additionally a randomly generated pattern of bad pixels (see Parameter BADPIX). Bad columns or rows of pixels can also be generated.

#### Usage:

creframe out mode [lbound] [ubound]
$\left\{\right\$
mean=? background=? distrib=? max=? min=? ngauss=? seeing=? mean=? sigma=? high=? low=?

mode

#### Parameters:

##### BACKGROUND = _REAL (Read)
Background intensity to be used in the generated data array. Must not be negative. (GS mode).
The number of bad columns to include. Only accessed if Parameter BADPIX is TRUE. The bad columns are distributed at random using a uniform distribution. [0]
Whether or not bad pixels are to be included. See also Parameters FRACTION, BADCOL and BADROW. [FALSE]
The number of bad rows to include. Only accessed if Parameter BADPIX is TRUE. The bad rows are distributed at random using a uniform distribution. [0]
##### DIRN = _INTEGER (Read)
Direction of the ramp. 1 means left to right, 2 is right to left, 3 is bottom to top, and 4 is top to bottom. (RA mode)
##### DISTRIB = LITERAL (Read)
Radial distribution of the Gaussians to be used (GS mode). Alternatives weightings are:
• "FIX" –- fixed distance, and

• "RSQ" –- one over radius squared.

["FIX"]

##### FRACTION = _REAL (Read)
Fraction of bad pixels to be included. Only accessed if BADPIX is TRUE. [0.01]
##### HIGH = _REAL (Read)
High value used in the generated data array (RA and RL modes).
##### LBOUND( 2 ) = _INTEGER (Read)
Lower pixel bounds of the output NDF. Only accessed if Parameter LIKE is set to null (!).
##### LIKE = NDF (Read)
An optional template NDF which, if specified, will be used to define the bounds for the output NDF. If a null value (!) is given the bounds are obtained via Parameters LBOUND and UBOUND. [!]
##### LOGFILE = LITERAL (Read)
Name of a log file in which to store details of the Gaussians added to the output NDF (GS mode). If a null value is supplied no log file is created. [!]
##### LOW = _REAL (Read)
Low value used in the generated data array (RA and RL modes).
##### MAX = _REAL (Read)
Peak Gaussian intensity to be used in the generated data array (GS mode).
##### MEAN = _REAL (Read)
Mean value used in the generated data array (FL, RP and GN modes).
##### MIN = _REAL (Read)
Lowest Gaussian intensity to be used in the generated data array (GS mode).
##### MODE = LITERAL (Read)
The form of the data to be generated. The options are as follows.
• "RR" –- Uniform noise between 0 and 1.

• "RL" –- Uniform noise between specified limits.

• "BL" –- A constant value of zero.

• "FL" –- A specified constant value.

• "RP" –- Poisson noise about a specified mean.

• "GN" –- Gaussian noise about a specified mean.

• "RA" –- Ramped between specified minimum and maximum values and a choice of four directions.

• "GS" –- A random distribution of two-dimensional Gaussians of defined FWHM and range of maximum peak values on a specified background, with Poissonian noise. There is a choice of spatial distributions for the Gaussians: fixed, or inverse square radially from the array centre. (In essence it is equivalent to a simulated star field.) The x-y position and peak value of each Gaussian may be stored in a log file, a positions list catalogue, or reported on the screen. Bad pixels may be included randomly, and/or in a column or line of the array.

##### NGAUSS = _INTEGER (Read)
Number of Gaussian star-like images to be generated (GS mode).
The output NDF.
##### OUTCAT = FILENAME (Write)
An output catalogue in which to store the pixel co-ordinates of the Gausians in the output NDF (GS mode). If a null value is supplied, no output positions list is produced. [!]
##### SEEING = _REAL (Read)
Seeing (FWHM) in pixels (not the same as the standard deviation) (GS mode).
##### SIGMA = _REAL (Read)
Standard deviation of noise to be used in the generated data array (GN mode).
##### TITLE = LITERAL (Read)
Title for the output NDF. ["KAPPA - Creframe"]
##### UBOUND( 2 ) = _INTEGER (Read)
Upper pixel bounds of the output NDF. Only accessed if Parameter LIKE is set to null (!).
##### VARIANCE = _LOGICAL (Read)
If TRUE, a VARIANCE component is added to the output NDF representing the noise added to the field. If a null (!) value is supplied, a default is used which is TRUE for modes which include noise, and FALSE for modes which do not include any noise. [!]

#### Examples:

creframe out=file ubound=[128,128] mode=gs ngauss=5 badpix badcol=2 max=200 min=20 background=20 seeing=1.5
Produces a 128$×$128 pixel data array with 5 gaussians with peak values of 200 counts and a background of 20 counts. There will be two bad columns added to the resulting data.

#### Notes:

• The Gaussian parameters (GS mode) are not displayed when the message filter environment variable MSG_FILTER is set to QUIET.

#### Implementation Status:

• The DATA and VARIANCE components of the output NDF have a numerical type of "_REAL" (single-precision floating point).

• This routine does not assign values to any of the following components in the output NDF: LABEL, UNITS, QUALITY, AXIS, WCS.