LMBSTA (Feb93)                   gongcor                  LMBSTA (Feb93)



NAME
    lmbsta -- Calculate statistics for an elliptic data window
    
    
USAGE
    lmbsta input inpcr otpcr deriv bb01  ...  bb14
    
    
PARAMETERS
    
    input
        List  of  input  pixel arrays containing full disk images of the
        sun.
        If N1 and N2 are the dimensions of the images,
        N1/4.LE.N2.LE.4*N1; i.e. the dimensions  must  be  approximately
        equal.
        N1.LE.1024; N2.LE.1024
    
    inpcr otpcr
        Inner ellipse, % of limb radius
        Outer ellipse, % of limb radius
    
    deriv
        Derivative option:
                DERIV=" "; no derivative
                DERIV="x"; derivative along the line direction
                        X_DERIV(IX)=-0.5*F(IX-1)+0.5*F(IX+1)
                DERIV="y"; derivative along the column direction
                        Y_DERIV(IY)=-0.5*F(IY-1)+0.5*F(IY+1)
                DERIV="r"; radial derivative from the ellipse center
                        R_DERIV(IX,IY)=COS(A)*X_DERIV(IX,IY)
                                        +SIN(A)*Y_DERIV(IX,IY)
                        where A=ATAN2(IY-YC,IX-XC)
                        where XC,YC are the ellipse center from the
                                limb parameters from the image header.
        Edge  handling  consists  of  continuation of the first and last
        row and column.
        Zero pixels are suppressed.  A  zero  pixel  contributing  to  a
        derivative   results   in   a  zero  derivative  which  is  also 
        suppressed in computing the statistics.
    
    bb01 ... bb14
        Bin boundaries for the histogram.
        The first bin boundary is the upper bound  of  the  lowest  bin.
        The lower bound of the lowest bin is INDEF.
        The  number  of  bins  (<=15)  is  determined  by  the number of
        monotonically increasing bin boundaries.
        The last bin boundary is the lower bound  of  the  highest  bin.
        The upper bound of the highest bin is INDEF.
        Consequently,  the number of bins is always one greater than the
        number of bin bounds.
    
    
IMAGE HEADER WORDS
    
    The following header  parameters  are  read  from  the  input  image
    header:
        FNDLMBXC, the x-coordinate of the center of the disk in pixels
        FNDLMBYC, the y-coordinate of the center of the disk in pixels
        FNDLMBMI, the length of the semiminor axis in pixels
        FNDLMBMA, the length of the semimajor axis in pixels
        FNDLMBAN, the ellipse rotation angle in degrees
    
    
DESCRIPTION
    
    LMBSTA  calculates  the  mean,  the  debiased  rms, the maximum, the
    minimum, and a histogram for a data window that is  defined  by  two
    concentric ellipses.
    
    The  limb  ellipse parameters from the header are used to define the
    window.
    
    The inner ellipse is obtained by multiplying  the  major  and  minor
    axes by INPCR.
    
    The  outer  ellipse  is  obtained by multiplying the major and minor
    axes by OTPCR.
    
    
EXAMPLES
    
    
TIME REQUIREMENTS
    
    
BUGS
    
    
SEE ALSO
    fndlmb
    lmbcor
    imstat
    imhist